Yard and Garden: April 28, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 28, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Dick Campbell, Owner of Campbell’s Nursery in Lincoln, NE

1. The first caller of the day has a Lilac that has bloomed in the past, but it isn’t blooming much. It has never been a reliable blooming shrub. What is wrong with it and how can it be fixed?

A: This plant was bloomed a few times in the fall, which would cut off the blooms for the following spring. However, this isn’t the only problem because for the past couple of years they have been better at timing their pruning. A late frost could have hit the blooms causing problems with bloom, it may reduce the overall bloom amount. Also, this could be a nutrient issue. A good fertilizer, such as bone meal, could be incorporated into the soil surrounding the plant to help with the nutrient availability.

2. A caller has ribbon grass that has died out in the center. This dead center has continued to get larger over the years. What can be done about that?

A: This plant needs to be divided. Many perennial grasses will develop a dead center when it is time to dig them up and divide them. The spring is a good time to do this for grasses. Iris plants will do this as well, they are best divided and replanted in the fall.

3. This caller has a weeping Norway spruce that is bending over heavily. Should it be trained to keep it more upright?

A: This is a typical growth habit for a weeping Norway spruce. They bend over more than some of the other weeping varieties. It would be good to put a small stake along the trunk of the tree to support it for more upright growth.

This caller also wanted to know what the timing was for spraying apple trees for Cedar-Apple Rust?

A: Now would be a good time. When the galls on the cedar rust have come out to look like a slimy glob in the spring rains it is time to spray. Those galls have just begun to open up and release the spores. For more information on cedar-apple rust, see this NebGuide.

Photo of Cedar Apple Rust Gall photo courtesy of Mike Lewinski via Flickr Creative Commons License

4. A caller has a cherry tree that has a split going up it and now it has sawdust around it on the ground.

A: Often we see insects in our plants as a secondary problem. What you are dealing with here, is most likely carpenter ants. They have come into the split in the tree and are making a nest in the rotting heartwood. The carpenter ants are not doing any more damage to the tree than what is already done. They can be killed by using an insecticide dust in the tree crack, such as sevin. However, the more concerning issue is the crack in the tree. If the tree is very large it may be a hazard. Tree removal may be necessary. If the crack is not very deep, it could be a frost crack which would be less hazardous.

5. Can you grow English Walnuts in Nebraska?

A: Yes, they can be grown here, it is most likely you will have to plant them from a seed as there aren’t many grown as plants for sale. Check with the Nebraska Nutgrowers Association for more information and seed/plant sources.

6. This caller has a blue spruce that is not growing well. It was planted 17 years ago and hasn’t grown more than a couple of feet in this time. What is wrong and can it be fixed?

A: The tree could be battling with too much brome grass growing around it and competing for nutrients and water. It would be beneficial to kill the brome grass and to add a mulch ring of 2-3 feet out and 2-3 inches deep around the tree to help reduce competition. This also could be a root issue that there would be no fix for. Often times, our trees are planted too deeply or grown in a container too long causing the roots to circle the tree. Once the tree is planted, there is no way to fix these conditions and the damage may not be present in the tree for 10-15 years after it was planted. This could be the case with this tree. Try adding mulch and ensuring proper irrigation through the growing season and it may come out of it.

7. A caller has a redbud that is 8 years old. The branches are dying and there are holes in the trunk. It seems that only one branch is still alive on the tree. What can be done for the tree? Or should it be removed?

A: The holes could be from borers that can be treated, but are often a secondary pest. If only one branch is left alive on the tree, it may be time to replant.

8. This caller is planting a new garden in an area that was a cornfield until this year. What do they need to do to the soil to plant in it?

A: Because this has been used as a crop field, I would advise a soil test to see where all the levels of pH, organic matter, Nitrogen, Phosphorus, and Potassium are at and to ensure vegetable crops will even grow in the soil that has been heavily planted for many years.

9. A caller is cleaning out dead and dying pine trees in a windbreak. Do the stumps need to be removed? What can be done to get it ready to replant?

A: If they are Junipers, or eastern red cedars, they can simply be cut off at ground level and they will not regrow. With some of our windbreak plants, they may need a stump treatment of 2,4-D or Roundup or a mix of the 2 products. If you are planning to plant a new windbreak where you removed these plants, it would be beneficial to grind out the stumps. If there is enough space, you can replant around the old stumps, just stay a few feet away from the stumps left behind if you don’t remove them.

10. What is the best care to give to seedling trees given to students for Arbor Day?

A: Grow the seedling in a pot for a year. When winter comes either plant the pot in the ground with heavy mulch or bring the container into the garage. Next spring, plant the seedling into the ground and protect it with fencing from rabbits and deer.

11. A caller wants to know how to control sandburs and where you can purchase milkweed plants?

A: Sandburs are controlled with crabgrass control products. As a preventer, using crabgrass pre-emergent herbicides will also prevent the germination of sandburs. If they have already germinated and are starting to come up, you can use a post-emergent herbicide for crabgrass such as quinclorac or Drive or Dimension. You should be able to find Milkweed plants at many local nurseries.

12. This caller has a white powdery substance on her peonies. What is it and what can be done for it? Also, she has a cherry tree that was severely damaged from deer, but now there are new suckers growing from the ground around it. Can those cherry tree suckers be grown into a new tree?

A: The white substance on the peonies would be powdery mildew. It is not very harmful to the plant. You can use a fungicide on it to control the spread of the disease. Also, make sure you cut off and remove the above ground growth that dies back in the fall to reduce the spores that overwinter for next year. The cherry suckers may not come up as the same species as you had planted and they may not be strong growing. Many of our fruit trees are grafted for a strong root system but desired traits from other trees. When suckers grow from the roots, you only get the type of tree that the main root system was and not the more desirable traits from the above ground portion of the plant. You can try it if you have room, but otherwise it would be best to start over from a new tree.

13. A caller put preen on his garden earlier this spring to stop the weeds. Now he is concerned if the plants he starts from seed this year will grow?

A: Unfortunately they will not grow where the preen is without extra care. You can either plant these plants from transplants or as seed in another location or in pots or you can till the bed to destroy the preen that is working as a barrier in the garden. Once you have gotten seeds to start growing in the garden, you can reapply the preen to reduce weeds later in the season.

14. A gentleman has holes around his house that are 1.5 inches in diameter and his tulip bulbs have been eaten off. What would cause these holes and how can the “critter” be managed?

A: This could be from either 13-lined ground squirrels or from voles. If it is voles, there would be runs in the lawn. Place a couple of snap-type mouse traps perpendicular to the runs in the lawn to manage the voles. If it is 13-lined ground squirrels, see this publication from UNL.

Tree Selection and Pruning

2014-06-12 16.10.39

Arbor Day is Friday, April 28th, 2017. Arbor Day is always an exciting day for me because I really appreciate trees and understand the real potential that can come from planting a tree. With Pine Wilt and the concerns of Emerald Ash Borer creeping closer it seems there is always a need to plant a tree, if not for you, then for future generations.

There are a lot of good trees to plant when you do plant a tree. The most important thing to remember when planting trees, is Diversity. When you go to purchase your tree, look around your yard and even your neighborhood. Try to avoid planting multiple trees of the same species, genus, or family of plants in the neighborhood and in your own landscape. You may enjoy Maples, but you want to make sure you plant other types of trees in your yard besides just maples to help avoid an issue that may arise should another pest come through like what we saw with Dutch Elm Disease or Chestnut Blight or now Emerald Ash Borer.

2014-10-06 15.27.18

Each year, ReTree Nebraska comes out with a new diverse list of trees that grow well in Nebraska and are often under-utilized. That list includes Baldcypress, Catalpa, Kentucky Coffeetree, Elm Hybrids, Hackberry, American Linden, Sugar Maple, Chinkapin Oak, Bur Oak, English Oak, Sycamore, Shantung Maple, Miyabe Maple, Gample Oak, Tree Lilac, Concolor Fir, Black Hills Spruce, and Ponderosa Pine. In 2017, ReTree Nebraska added Turkish Filbert including other nut trees such as Hickory, Chestnut, Pecan, Buckeye, and Walnut to the list of good trees to plant in Nebraska. There are a lot of other great trees to use in your landscape, this is just a short list.

Turkish Filbert is a unique, under-utilized tree in Nebraska. It grows up to 40-50 feet tall and 30-50 feet wide. It has large, bright green leaves that turn yellow in the fall. This tree has catkin flowers, like a cottonwood.  It has edible nuts that are produced in a cluster of 3-6 and have a spiny husk that covers the nuts. Often squirrels eat the nuts, but they can be roasted and eaten by humans. This tree is most commonly used as a shade tree or a specimen tree in a landscape.

Another thing to think about with our young trees, is pruning. Eric Berg, a community forester from the Nebraska Forest Service wrote a great article on pruning young trees. We need to start pruning our trees when they are young to minimize tree wounding and cause the trees to grow stronger, mature growth. A tree planted in a landscape setting, rather than being planted in a forested area, will grow out more than up and not develop a strong central leader. Often our trees develop multiple leaders that lead to weak growth that can easily be broken in storms. We saw the damage from weak branch attachments and poor growth in our ice storm this past winter.

pruning tools-K. Todd

Photo courtesy of Kim Todd, UNL Department of Agronomy and Horticulture

We can prune a tree when it is young to help prevent some damage in future storms. If you would like to learn more about pruning young trees, Graham Herbst, from the Nebraska Forest Service, will be in Beatrice to teach us about pruning young trees on Monday, June 19th from 6-8 pm starting at the Gage County Extension Office. He will cover how to set pruning objectives, determining a pruning cycle and dose, strategies for specific trees, and how to execute your plan with proper cuts. There will also be a hands-on pruning demonstration at the end of the classroom portion. If you are interested in this program, please call the Gage County Extension Office at 402-223-1384 to sign up.

Yard and Garden: April 14, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 14, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: George Pinkerton, Director of Landscape Maintenance at Downtown Lincoln

1. The first question came from a caller wondering what the timing is for crabgrass preventer?

A: Typically we go with mid-to late April for application of crabgrass preventer. Crabgrass germinates when soil temperatures reach 55-60 degrees Fahrenheit. In most of the Southeast Nebraska area, we have just recently hit that. Anytime in the next couple of weeks would be fine to apply your crabgrass preventer. It might be best for control to apply a split application this year. For a split application, apply half of the recommended rate now and the other half of the recommended rate 8-10 weeks later. The split application will give you a longer season of control for crabgrass and other annual grassy weeds.

2. A caller was wondering about their gladiolus bulbs. They have had problems with thrips insects in the past and they had heard they should soak their bulbs in lysol to control them. Is this a good method of control or is there something better?

A: As it turns out, you can soak the corms in a solution of lysol water prior to storage of the corms over the winter months, according to the University of Minnesota Extension. You can also dust the corms with a sevin dust prior to storage in the late fall, store them with mothballs, or store them at colder temperatures such as 35-40 degrees F as well. If you are looking for control at this time, it would be best to spray the plants as you see the streaking damage beginning from the thrips feeding in the spring and summer months. You can use any general insecticide for this.

3. This caller has a sugar maple that was hit with hail 5 years ago and now has a great deal of damage to the trunk of the tree. They have sprayed the trunk with a sealant and used a wrap. Will the tree survive or should it be removed now?

A: At this point, I would observe the tree to watch for signs of death occurring through the tree. The damage that is there cannot be fixed now that it has occurred. If you don’t like the look of the damage you can remove and replace the tree or you can wait until it starts to dieback. It is hard to say how long the tree will live now that the damage has occurred.

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Bare lawn in need of overseeding.

4. A caller wants to reseed. What seed should he use?

A: For a new seeding, use a turf-type tall fescue or a Kentucky bluegrass. Use either 100% of either of these types or use a 50% mix of the two. For more information, see this article from the UNL Turfgrass Department on Choosing Grass Seed.

5. A caller has a section in fairly high shade that died out last year. Why and can it be reseeded?

A: In locations of very high shade turf doesn’t always do well. The caller said this had been growing there for 25 years so it could have been a fluke that the lawn died out last year. You can reseed now with regular turf or you can use a shady groundcover such as a carex species.

6. When is the time to transplant coreopsis to a location with more sun?

A: Now would be a great time. Mid April through mid-late May is a great time to transplant perennials.

7. This caller has some large pin oaks that need to be pruned to make it easier to mow underneath the tree. Is it too late now to do that?

A: Yes, it would be better to wait until late fall to prune the oaks now. Oak trees are susceptible to oak wilt which is spread by a beetle in the summer months. It is best to avoid pruning them at this time of the year to reduce the incidence of disease.

8. What kind of tree would be a good choice for shade production in a backyard?

A: Any of the oak species, shagbark hickory, sycamore, Linden, Kentucky coffeetree, Black locust, thornless honeylocust, hackberry, and many others.

Curly Dock, Steve Dewey, Utah State Univ, Bugwood

Photo of Curly Dock from Steve Dewey, Utah State University, Bugwood.org

9. A caller wants to know what to do for management of curly dock?

A: 2,4-D or Trimec can be used this time of year or use a mixture of 2,4-D and Roundup.

10. What do you do for thistles growing throughout a yard?

A: 2,4-D or Trimec, but these products are best used in the late fall or before flowering. Thistles are a biennial so if you can dig up the plants as a rosette in the first year of growth they will die.

11. This caller has cherry trees that are suckering. Can one of the suckers be dug up now to start another plant?

A: Yes, it can be done now, but fall would be a better time of the year for this. If it needs to be done, it can be done now. However, depending on the type of sucker growth, the new plants may not be the same as the original plant or they may have weak growth.

12. An email from a listener asked what is wrong with his pin oak that has leaves that are curled up like they were hit with a spray? He wondered if they were too close to the windbreak that is 20 feet away? Is there a certain distance you want to stay away from your windbreak when planting other trees?

A: You do need to give your trees space to grow, but pin oaks are often planted as a third, interior row to a windbreak. The spacing between rows would be 15-20 feet, so the proximity to the windbreak would not be a problem in this instance. Most of the time if a tree is lightly hit with spray drift from a pesticide, it will not show in the tree every year unless it is hit every year. In this case, I would ask for a picture or sample to help with further diagnosis.

13. When is the best time to transplant peonies? Why isn’t the rhubarb up yet?

A: Fall is the best time to transplant peonies. If necessary for construction or moving purposes, it can be done yet this spring. Plant them at the same depth at their new location. As for the rhubarb, give it a few more weeks to see if it comes up before giving up on it. If it is in a location that is more exposed to cold winds the soil may have not warmed up enough yet this spring.

14. This caller wants to know what type of fertilizer to use in a garden?

A: A low grade, balanced fertilizer is best for a garden, like a 10-10-10 or 12-12-12 with slow release fertilizer is best.

15. The final caller of the day wanted to know if now was the time to fertilize pecans?

A: Many of the trees in our environment have sufficient nutrients for growth and so fertilization on these pecan trees may not be necessary. If you are concerned with the growth of the tree, take a soil test to see where the fertility levels are. If it is growing fine, don’t fertilize it because our trees and other plants can be over-fertilized which can cause injury or even death.

Yard and Garden: April 7, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 7, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Hosts: Jonathan Larson, Extension Entomologist from Douglas-Sarpy Counties & Jody Green, Extension Entomologist from Lancaster County

1. The first question was to see if we could guess the caller’s favorite insect that was described as a moth with large, light green wings and feathery antennae?

A. This is a luna moth

2. A caller has moles in the yard and wants to know how to manage them?

A. A harpoon type of trap can be used, but should be prepped ahead of installation. This trap tends to work best if you stomp on a run to determine if it is an active run.  If it gets pushed back up, it is an active run. Stomp on this area a couple of more times and then set the trap to ensure the mole moves through the area. For more information on moles, click here for a publication from UNL on moles.

3. This caller wants to know how to get rid of creeping charlie in a lawn?

A. Triclopyr or a 2,4-D product can be used in the fall. For best control, use the product twice in the fall 2-3 weeks apart. September 30th and October 15th would be good dates for application. This is a tough weed to control, so it will take multiple years of multiple applications. A spring application of either of these products can be used as well to knock the weeds back for this year.

4. When can you transplant daylilies? Can they be planted into an area on the east side of the house with rock mulch?

A. Wait a couple of weeks until mid-late April to transplant them when the temperatures have warmed up more. Also, as long as the area is receiving at least 6 hours of sunlight daylilies will grow fine. This is a tough plant that will grow well in most conditions.

5. A caller has strawberries that had botrytis last year. When should they be sprayed to prevent the disease this year?

A. Apply from 5-10% bloom until flowers have finished blooming. For more information see the Midwest Small Fruit and Grape Spray Guide from Midwest Universities including UNL.

6. This caller has a pear tree that last year had orange spots on the leaves later in the season. What is this and how can it be controlled?

A. This is due to a rust disease, Cedar-Hawthorn Rust. It is more common in years following a wet spring. The timing for management is in the spring, May and June. See this NebGuide on Cedar-apple rust and related rusts of apples and ornamentals.

7. A caller has started corn, watermelons, and cantaloupe indoors from seed. The seedlings are getting quite large. Can they be transplanted outdoors now?

A. Unfortunately it is still too cold to plant these crops outdoors. These are warm season crops that should not be planted until early May after the frost-free date. These crops could be direct seeded at that time or transplanted but they tend to not do well as a transplant.

8. A caller has 2-year-old rhubarb plants that have come up and have thin, limp stalks. What is wrong with the rhubarb?

A. This could be due to crown rot. Rhubarb is very sensitive to high moisture soils and will often develop a crown rot in these situations. Those plants that have limp stalks should be removed and you can replant in a new location where it has more well-drained soil.

Bagworm4

Bagworm

9. When and what should you spray for bagworms?

A. May-June is the time frame for treating bagworms. It is best to spray them when the new bags are 1/2-1 inches long. Longer than that and they won’t catch as much of the pesticide to die as well. For spray choices, any general insecticide will work, but using Bt would be the least damaging to other insects because Bt only affects insects in the Order of Lepidoptera which includes butterflies, moths, and skippers.

10. A caller has Asparagus that has a green moss-like structure growing on top of the ground around it. What is it and what can they do for it?

A. A picture would be helpful in identifying this pest. If it is actually a moss, they may look into the water in the area because it is likely that it is too wet. If it is a weed, pull or hoe the weed and then add a layer of mulch to prevent further weeds from coming in.

11. This caller wanted to know what to do to grow bigger onions and if they should put Epsom salt on their tomatoes to help them grow more?

A. These onions are growing 3 inches apart, they should be spaced out more for larger sized onions. Place plants or sets 1-6″ apart in the rows, and 12-24″ between rows. For bulb production, plant onions in early spring. The number of leaves that form prior to bulbing determine the ultimate onion size. Since bulbing in each cultivar is triggered by a specific daylength, early planting is the most effective method of increasing bulb size, by allowing more time for leaves to form. If the onions do not grow well before bulb induction, the final bulb size may be smaller than desired. Avoid sets more than ¾ inch in diameter because they are likely to produce seed stalks.

As for the Epsom salt on tomatoes, no you should not apply this to your soil when you plant tomatoes. Our soils have a sufficient amount of magnesium and sulfate, which are the 2 ingredients in Epsom salt, so there is no need to apply more. If you need fertilizer, use a general fertilizer from the nursery or garden center.

12. A caller has a Japanese maple that was injured last May when the leaves curled up and fell off. The leaves never regrew through the summer last year. Will it come out of it?

 A: If it happened that early in the year last year and didn’t put on new leaves, it may be dead. Give it time this spring to green up. You can check if the tree is still alive by scraping the bark on a branch, if there is green underneath it is still alive, if there is brown it is dead.

13. What can you do to manage windmill grass?

A: Windmill grass is a perennial weed. You can use roundup and overseed or use a product containing mesotrione or Tenacity that will not harm your turf. Use the Tenacity in the late spring.

14. This caller wanted to know what to use for a pre-emergent herbicide in a strawberry patch?

A: Preen that is labeled for use in a vegetable garden would be allowed in a strawberry patch. The best control for weeds in strawberries would be to use mulch.

15. Can you use plants to repel insects?

A: Some plants may deter a few insects for a short time, but no, the plants are not concentrated enough to work against the insect pests.

16. A caller has an arborvitae that turned brown on the North side last fall. Will it be ok?

A: This could be due to bagworms or due to environmental stress. Arborvitae trees don’t like the sudden cool down in the fall and it can cause part or all of the plant to die quickly. Unfortunately, if the tree has turned brown all the way back into the trunk, the tree will not regrow on that section. Removal and replacement may be a better option for this plant.

17. This caller wanted to know when they can reseed their lawn and with what?

A: Mid to late April is the best time to reseed a lawn in Southeast Nebraska. Reseed with 100% Turf-type tall fescue or 100% Kentucky bluegrass or a 50% mix of each.

Squash bug-NH-pic monkey

18. A caller asked what to do about squash bugs in their vegetable garden?

A: Fall sanitation and cleaning up the garden will help a lot to reduce the eggs in the soil around your garden. When they do start coming out in the summer, you can use sevin, eight, or bifenthrin to control them. You will have to spray every 10-14 days through the growing season. Watch the Pre-Harvest Interval to know when you can harvest after spraying a chemical on your plants. You can also smash or remove the eggs you see which are tiny, football-shaped bronze colored eggs on the underside of the leaves typically found in the crotch of the leaf veins.

Which Herbicide to use…

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Photo by Nic Colgrove

Spring is coming. And with the onset of warm weather and more spring rains, comes many different lawn weeds. Each year we tend to find new herbicides in the garden center of our favorite stores. However, when dealing with pesticides, it is very important to know what you are purchasing and how to correctly use it so as to not harm the environment, pollinators, and beneficial plants.

One of the things we all need to remember when using pesticides is to use the right product for the job and to know what you are using. To use the trade name Roundup isn’t going to be enough anymore. There are a lot of new Roundup brand products that each have a different combination of chemicals.

Roundup 365 is a new product from Scotts that contains both glyphosate, which is the active ingredient in the general Roundup product, as well as Imazapic. Imazapic is a selective herbicide used to control annual and perennial grasses as well as some broadleaf weeds. It has a trait that allows it to last longer in the soil than a regular glyphosate product which is essentially deactivated when it hits the soil. In accordance with the label, Roundup 365 should only be used in cracks and crevices in sidewalks, driveways, walkways, and tennis courts, amongst patios and paths, along fences, foundations, curbs, retaining walls, and landscape borders, and in gravel areas and parking areas. It is not to be used in areas where planting or seeding will occur for the next year or in the root zone of plants or in any other garden setting where desired plants are. Also, be careful when applying this to fenced areas as it should not be applied where there are desired plants on the other side of the fence that could be damaged with the application of this product.

Roundup for Lawns is another new product made by Scotts that actually contains no glyphosate. Roundup for Lawns contains MCPA, Quinclorac, Dicamba, and Sulfentrazone. MCPA is a herbicide similar to 2,4-D for broadleaf weeds. Quinclorac is a post-emergent crabgrass and annual grass herbicide. Sulfentrazone is the active ingredient found in Sedgehammer that is often used on yellow nutsedge. Dicamba is one of the 3 active ingredients in Trimec that is used for broadleaf weed control in a lawn. This product can be used over an established lawn because it has no ingredients that will kill established turfgrass.

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*Reference to commercial products or trade names is made with the understanding that no discrimination is intended of those not mentioned and no endorsement by University of Nebraska–Lincoln Extension is implied for those mentioned.

Dicamba is a pesticide that we should be very careful with, as well as any pesticide that contains dicamba which includes Roundup for Lawns and Trimec. Dicamba can turn into a gas and move to non-target plants as a vapor in temperatures of 85 degrees and above. This volatilization can occur for the day and even a couple of days after application. So Dicamba products shouldn’t be used in the summer months. Also, be very careful with Dicamba products in your lawn around trees and shrubs. This product can cause injury to these plants when it moves through the soil and comes into contact with the roots. Limit use of this product to no more than twice per growing season around tree roots to avoid injury.

Each of these Roundup products are labeled for different uses. So, make sure that you always read and follow the label instructions provided with the product to ensure that you are using the product correctly and so that you don’t harm the environment or any non-target plants. Always keep the label and product instructions with the product so you will always know how and where to properly apply it.

*Reference to commercial products or trade names does not imply endorsement by Nebraska Extension or bias against those not mentioned.

Yard and Garden: March 31, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for March 31, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Natalia Bjorklund, Nebraska Extension Educator in Dodge County

1. The first question was when can we begin applying crabgrass preventer and fertilizer to our lawns this spring?

A. These are both best applied in late April to early May. Crabgrass will not germinate until the soil temperatures are consistently at 55-60 degrees Fahrenheit.

2. A caller wanted to know if he should mulch his asparagus and if he can use ash wood mulch around his asparagus?

A. Yes, mulch is one of the best ways to manage weeds in an asparagus patch. Ash wood chips would be fine. You do want to avoid Walnut wood chips because walnuts produce juglone which is a chemical produced by the tree to act as a weed control for nearby plants. This helps walnut trees with competition in the wild.

3. This caller has a goldenrod that has grown too large and messy for the area where it is planted. How can it be killed and what Goldenrod would be a better choice for a less messy plant?

A. 2,4-D or simple hand removal should kill the plant. When purchasing a Goldenrod plant in the future, any of the varieties would be better than the straight species. Fireworks is a nice, open goldenrod. Wichita Mountains and Baby Blue would be good choices as well.

4. Is it too early to transplant hostas? When should you cut back warm season grasses?

A. Wait a couple of weeks to transplant the hostas until the soil has warmed up a little more. You can cut back the ornamental grasses anytime now. It is better to get the old growth cut off before growth resumes so you don’t cut off the new growth. For ease of cleanup with the ornamental grasses, wrap string or twine around the plant before cutting off the old materials so it stays together when taking to the compost pile.

5. A caller wanted to know how and when to prune roses?

A. Wait until a little later into April to start pruning them. It depends on the type of rose to know how to prune them. This sounds like a climbing rose which can be pruned back about 1/2 to reduce the size. Wait until they start greening up to know which areas of the canes have died back, the dieback should be removed as well. If the canes are long and lean over mowing areas or other things, they can be tied up to a trellis.

6. This caller wanted to know how to get rid of cockleburs?

A. While talking with the caller, it came up that the plant had very small yellow flowers on it and there were spines over the plant except right at the soil surface. This plant is in fact buffalobur, not cocklebur. These are easily pulled up if you pull where there are no spines. A 2,4-D product could also be used if there was a large amount of them in the lawn.

buffalobur, Howard F Schwartz, Colorado State Univ, Bugwood

Buffalobur plant from Howard F. Schwartz, Colorado State University, Bugwood.org

7. A caller wanted to know if they should water in their crabgrass control?

A. The label will explain to you how a product should be applied for best efficacy. Always read and follow the label instructions to apply correctly. For many of the crabgrass preventers, they would need to be watered in, but again, check the label to be sure.

8. When should asparagus be fertilized?

A. Apply a general fertilizer or a composted manure to the bed after the last harvest or sometime in the fall.

9. This caller has mulberries growing in the windbreak. After they are cut down, what kind of stump treatment should be done to keep them from regrowing?

A. 2,4-D concentrate should be used as a stump treatment. This will take multiple applications and will be more effective if done in the fall. Each time the 2,4-D is reapplied it should be applied into newly drilled holes or to a freshly cut area of the stump.

10. A caller has cedars growing in their landscape. Under the cedars there is bare ground. What can they plant in that area to avoid weeds coming in?

A. The cedars are going to keep that area quite dark and the cedars will take the majority of the water in the soil so mulch would be a good alternative. If plants are desired, use a shade tolerant groundcover such as wintercreeper or vinca vine or perennial plants such as bleeding hearts, hostas, coral bells, jacob’s ladder, and others.

11. This caller has tiny cedar trees coming up throughout the lawn. How can they be controlled?

A. Cut them off at ground level. If a cedar is cut below any lateral growth it will not regrow. Mowing over them wouldn’t be low enough.

3-step pruning cut

Proper pruning cut, University of Missouri Extension

12. When is the best time to prune a maple tree that had a branch break in a storm?

A. As soon as the storm has passed and it is safe to do so, you should remove a branch that broke in the storm. If the damage occurred in a winter storm, let the ice and snow melt off first. Then, hire a certified arborist to come out and make a good pruning cut so that the tree can seal off the wound quickly and fully.

13. A caller has a hibiscus tree that is turning yellow and many of those yellow leaves are falling off the tree. It was moved indoors during the winter months in an area of the house with low sunlight. What is wrong with it and will it survive?

A. Hibiscus plants would need more sunlight than what it has received through the winter. It should be fine once it gets more sunlight. As the days get warmer, you can move it outdoors for more intense sunlight. It should be fine once it gets moved to better growing conditions.

14. This caller has a weeping willow tree that they would like to prune up a little. When can they prune it?

A. The weeping branches shouldn’t be pruned up too much or they could lose their weeping habit. Willows tend to have a heavy sap flow in the spring if they are pruned then, so it would be best to wait until later fall to prune a willow.

15. This caller has grasses that are coming up among the gravel paths around his daylily patch. What can he use to prevent those plants from coming up?

A. Preen is a great way to stop the germination of annual weeds, such as many of our weedy grass species. If they come up before the preen gets put down or if they grow as a perennial weed, you can use a post-emergent herbicide. If it is a grass that is growing out of place among daylilies, you can use Grass-B-Gon or a similar product to kill grasses.

henbit, steve dewey, Utah State Univ, Bugwood

Photo of henbit is from Steve Dewey, Utah State University, Bugwood.org

16. What can be done to manage henbit?

A. At this time of the year, there is nothing very effective at controlling henbit. Henbit is a winter annual plant, meaning that it germinates in the fall and flowers and produces seed in the spring. It dies with the summer heat. As we are now seeing the purple flowers from henbit, there is no need to control what you are seeing. The seed is already present in the lawn for next year and what you would be spraying will die soon. You can hand pull it now and spray with a 2,4-D product late in the fall.

17. This caller has moon flowers that had a lot of hornworms on them last summer. What can be done this year to reduce the number of hornworms?

A. Just because there were hornworms there last year doesn’t necessarily mean you will have a lot this year. Hornworms are sporadic pests. They are easily controlled by hand removal. You can also use sevin or eight or any other general insecticide. Use Bt to protect other pollinators as Bt is only harmful to insects in the order Lepidoptera which includes butterflies and moths.

18. What do you do for bindweed in a vegetable garden?

A. If you haven’t planted yet this spring, you can roundup the plants before you prepare the soil for the summer vegetables. The plants will probably still be a problem later in the year as this is a difficult pest to control. When it comes back in the summer, you can carefully use roundup through the growing season. You can paint the glyphosate product onto the leaves of the bindweed avoiding spraying the desired plants.

Yard and Garden: March 24, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for March 24, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Cole Thompson, Assistant Professor of Integrated Turfgrass Management at UNL

1. The first question of the year was a caller who had 2 peach trees that were three years old when they died last year. He cut the trees off and now there is suckers coming up from the ground where those trees were. Will these trees grow and produce peaches?

A. These trees will grow and will most likely produce fruit. However, they will not be a strong growth and the peaches produced may not be the variety that he originally planted. Many of our fruit trees are grafted to a hardier rootstock. If they die back or produce suckers, that growth will be the type of tree that the roots are not the type that the scion, or top part of the graft union, was. Also, because it is from a sucker, it is not going to grow as strong and upright as the main tree. He can try to keep them going but it would be best to plant new trees as well, if he has the space for both, he can keep both the suckers and new trees. If he only had room for a couple of trees, I would suggest starting the trees over from new trees.

2015-06-25 10.19.56

*Reference to commercial products or trade names is made with the understanding that no discrimination is intended of those not mentioned and no endorsement by University of Nebraska–Lincoln Extension is implied for those mentioned.

2. This caller wanted to know what the difference is between Roundup and Roundup 365?

A. Roundup 365 contains a chemical called imazapic which gives the traditional glyphosate product more of a soil residual. The Roundup 365 is labeled only for use on and around hardscape areas such as patios, gravel paths, and driveways. The label claims that it lasts in the soil for up to 12 months, so it should not be used around trees, shrubs, or areas you plan to reseed. Regular Roundup can be used in an area around plants and where you plan to seed after the recommended wait time. You would need to be much more careful with the Roundup 365 because of the soil residual around other plants.

3. A caller has pussy willow branches that were brought indoors and placed in water to begin rooting. They have now developed roots. Can they be planted outdoors now?

A. Yes, as long as the roots have begun to form and the ground can be worked, it would be fine to plant them outdoors now.

4. When is the best time to reseed a Fescue lawn in Southeast Nebraska?

A. Fall is the best time to reseed a lawn, but it can also be done fairly effectively in the spring. It is harder in the spring due to the weeds that compete with the grass seedlings. If you plan to reseed in the spring, it is best to wait until late April to early May for that. If you seed earlier in April, increase the seeding rate to compensate for the loss due to the colder temperatures. When you seed, you can apply tenacity or a mesotrione product to the seedbed to help with weeds. Tenacity is safe for use at seeding. It is also a good idea to seed with a starter fertilizer to help get your seed started strong.

5. This caller has a birch that was cut down last fall. The remaining stump is oozing a lot of liquid right now. How do they kill the birch entirely to stop the liquid from oozing out of the stump.

A. Birch trees are one of the species of trees that tend to “Bleed” heavily in the spring if they are pruned. They have a high sap flow in the spring which will lead to the oozing of large amounts of sap through any open wounds. On a normal pruning cut to a tree with high sap flow, it is not harmful to the tree. This tree still has living roots and the wound from cutting it off is exposed so the sap still will flow through. This tree either needs to be treated with chemicals to kill it or the stump needs to be ground out to stop this sap flow and to be able to plant new plants in the area. You can drill new holes into the tree and apply 2,4-D to those holes to start to kill the tree. With chemicals, it will take a few years to fully kill the stump.

6. Can raspberries be transplanted now?

A. Yes, raspberries should be planted as early as the ground can be worked in the spring, so now would be fine. It is best if the soil was prepared last year by spraying all the weeds and incorporating organic matter. This will help to ensure you have a raspberry planting to last many years.

2016-11-22 16.59.14.jpg

7. A caller planted grass last fall and held the seed to the seedbed with a biodegradable plastic barrier designed for seeding turf. However, now the plastic is not breaking down and it is getting stuck in the lawnmower. Is there anything they can do to break it down quicker? It will disturb the lawn too much to try to pull it out now.

A. Pulling it out without disturbing the lawn would be the quickest, but if that is not safe to do without tearing up the lawn, that isn’t the best option. Try to water it down or hope for rain, the moisture may help to break it down faster than it sitting dry. This winter was quite dry which may have delayed the breaking down process.

8. This caller had a giant tree fall in his yard. He has removed most of the tree but about 5 feet of the trunk is still standing in the yard. What can he do with the stump?

A. It would be best to cut that trunk off at the ground level and grind the stump out so that you can replant either with turf or with a new tree. If you don’t want to grind it out now or replant, you can cut it down to the ground level and place soil over it to allow it to naturally break down under the soil.

9. A caller has been growing watermelons but they tend to wither and die early in the year. What is wrong and how can he improve his crop?

A. It sounds like this caller has squash vine borers that get into his vines in the summer months. Squash vine borer is a type of moth larvae that gets into the stem of the vines and blocks the movement of water and nutrients through the plant. They are very common in melons, squash, cucumbers, and pumpkins. To avoid the damage from this insect, use a spray or dust formulation of sevin or eight on the base of the plant regularly through the growing season starting in June. You can also use aluminum foil or a toilet paper tube around the base of the plant to act as a barrier between the plant and the female squash vine borer adult who is trying to lay her eggs on the plant.

10. This caller has 25 bur oak trees that were planted 4 feet apart with the idea that some would die to space them out further. Most did not die and are still planted too closely. Will they grow that close together or should some be removed?

A. Bur oaks grow quite large, but in a forested area they will grow fairly close together. They will grow this closely together, however it will shade out many of the branches and it will cause conditions that are conducive to diseases when trees don’t have the space to have good airflow. It would be best to remove some of the trees so that the trees left behind are given 20 feet or more between them. They are only 10-12 feet tall at this time so they would still be fine to be spaded out and transplanted to another location if you can find someone to spade them and someone to plant them somewhere else.

11. Is it too early to plant onions? Is it time to cut back mums that are left from last fall?

A. Late March to early April is the best time to plant onions. Wait to cut back perennials from last fall. The dead plant material will protect them from freezing temperatures for another week or two. The plant material can be removed in the beginning to the middle of April.

12. This caller has a yard with high dog traffic. What type of grass would be best to stay growing through the dog traffic?

A. High traffic lawns will decline. Increasing the fertility will improve growth in this area. Also, if you could limit the traffic patterns from time to time through the lawn, this would help as well. Kentucky Bluegrass will recover better in high traffic areas.

13. A caller has a bean field area that he is trying to turn back to a grass area. What type of grass would do good in this area for an non-irrigated recreational area on an acreage?

A. Buffalograss would be great for an acreage area. Once it becomes established it wouldn’t have to be irrigated much or mowed at all. It is a very low maintenance grass species that is native and you can choose many different newer varieties. UNL has good seed selections. Because this was a bean field it might be over-tilled so a roller may be necessary to firm the soil up before planting. Buffalograss is a warm season grass so it should be seeded May 1st.

14. The final caller of the day has an established cedar windbreak. Some of the trees were removed recently and there is a bare area in the nearby trees where they were shaded out from the removed trees. This area is only 7 feet from the house. What can be planted in place of these trees to help block the bare area in the windbreak?

A. Because this is so close to the house, don’t go with anything too big. A larger shrub may be a good choice such as a viburnum, serviceberry, some dogwoods or even some lilacs may help fill in. Some slender growing trees may also work, but full size trees may grow into the house.

Henbit?!

Henbit from canva

It’s spring, finally! I know our winter wasn’t terrible this year, but I always look forward to spring. That is such an exciting time of the year, all of our plants are greening up and the early blooming trees, shrubs, and bulbs are beginning to show us their beauty for the year. However, not everything about spring is fun and games. This is the time of the year I always get calls about that dreaded purple flowering weed in our lawns and gardens.

Henbit is the purple blooming weed that shows its ugly face very early in the spring. This is the weed that will cover crop fields early in the spring with large expanses of purple blossoms. This weed is also quite prevalent in our lawns and gardens.

henbit, steve dewey, Utah State Univ, Bugwood

Henbit is a member of the mint family, which means that it has square stems. It has leaves that are rounded with a scalloped edge and they are arranged oppositely along the stem. It has a small purple flower with darker colored purple spots on the lower petals of the flowers. Henbit is often confused with creeping Charlie or ground ivy, which is a perennial weed from the same family with purple colored flowers as well. The differences between the two are that creeping Charlie is a perennial so it blooms later in the year than henbit and creeping Charlie has flowers that are more blue and henbit flowers are more purple.

Henbit is a winter annual. This means that henbit only lives for one growing season, but it’s development is different from something like crabgrass which is a summer annual. A winter annual is a plant that germinates in the fall and grows a bit before basically becoming dormant for the winter months. Very early in the spring, henbit will start to grow again, produce flowers which produce seed for the growth to come next year and then it dies. A winter annual dies as soon as the weather starts to warm up in the late spring whereas a summer annual germinates in the spring and goes through it’s lifecycle through the summer months, dying with our fall frosts.

The problem with henbit is that by the time we see it, or rather see the beautiful purple flowers, it is too late to treat it this year. As I said, henbit dies when the weather warms up, so why spray it with a chemical when it is going to die in a few weeks anyway. The fact that it is noticed when it is blooming shows us that it is already producing seed for next year, so killing the existing plants does nothing for the future generation of this plant. However, pulling the plant would be a fine management practice in the spring months.

Henbit is a plant that tends to grow in the areas where grass typically dies out. Areas around sidewalks and driveways or areas where people tend to cut the corner around sidewalks are locations where the turf gets worn down and the henbit excels. Henbit is also often found along the foundation of a house or in a garden area with exposed soils. If we can do things to keep your grass growing in these locations or use other plants or mulch to cover the bare soil, the henbit will struggle. Using a pre-emergent herbicide for broadleaf weeds in the fall will also help reduce the seed germination. Finally, using any broadleaf post-emergent herbicide later in the fall after the henbit has germinated, such as 2,4-D, will kill henbit as well.

Nebraska Weather Effects on Plants

Crazy Weather blog

This year the weather has been crazy. We saw 70’s in February followed by 30’s and snow in the middle of March. The warm weather was great, but it got all of us in the mood for spring, including our plants. Now that we have seen such a cool down, our plants may be the ones most affected.

We have seen early budding in many of our shade trees and shrubs, which often happens with above average winter and spring temperatures. This can be problematic for the plant. If the swelling or opening up of buds occurs prior to a cold snap, it can cause damage to that particular bud. If those buds that were opening up were flower buds, we may lose the flowers on that shrub or tree for the year. However, if those buds were leaf buds, those plants may be set back on their emergence and growth for the year. If leaf buds were damaged, a healthy tree will set new, secondary buds to push growth but it will be later in the season than normal. As long as the tree is healthy it will be fine. But, there is nothing you can do to stop this condition.

Red maple, bugwood

Photo from: Chris Evans, Illinois Wildlife Action Plan, Bugwood.org

This warm up, cool down cycle is stressful to our plants. So, it is a good idea to help keep your plants otherwise healthy. Make sure your trees and shrubs are properly mulched and kept well watered in the absence of rain.

Another issue that we are dealing with this spring with the rapidly changing environment, is the advanced emergence from dormancy of spring bulbs prior to this latest cold snap. There is nothing you can do regarding this issue either. The bulbs that have already begun to bloom may lose their flowers early or have some freeze damage. These bulbs may also experience some leaf dieback. Tulips and daffodils are normally a spring blooming plant, so they are accustomed to normal spring freezes adapting to temperatures as low as the upper 20’s. However, if we see anything lower than that, these plants may exhibit freeze damage on the leaves, showing up as white, limp leaves. Do not cut back the damaged leaves until the foliage dies back on its own.

Finally, we have started to see many of our perennial plants emerging and greening up for the spring already. Much of this growth occurred before the cold snap last week. As for these plants, I would advise you to just leave them alone. If there is a forecast for very low temperatures, it would benefit the plants to add additional mulch or a row cover over them for the overnight hours, pulling that back during the day as the temperatures warm up. If you didn’t remove the plant material last fall, leave it there now until the spring, even as they green up below it. If you expose the crown of the plant that has been covered by the dead plant material all winter long, cold snaps will be more problematic for the plants. The dead plant material and extra mulch the plant has had over the winter months will protect it from freezing and thawing and from very cold temperatures this late in the season. It is best to wait until we are more consistently facing spring weather before removing this plant blanket they have had all winter.

Do prune this…Don’t prune that

2013-05-09 10.12.37

Spring will be here before we know it. With all the warm weather lately, it is hard to remember that spring has not already sprung in Southeast Nebraska. But, with the warmer weather, there are a few things we can do in our landscapes and a few things we should avoid.

Don’t prune spring blooming shrubs this time of the year. Plants such as lilac, forsythia, spring blooming spirea, and some hydrangeas produce flowers in the fall of the previous year to bloom early in the spring. If you prune these plants now, you will cut of the flower buds and not have those flowers to enjoy this spring. So avoid pruning those shrubs in the spring. Spring blooming shrubs should be pruned immediately after they finish blooming in the spring. This will allow for the best growth of the plant and for best flowering each year.

Forsythia-Richard Elzey, Flickr

Forsythia Flickr image courtesy of Richard Elzey per CC license

Prune trees this time of the year. February and March are the best months of the year to prune deciduous and fruit trees. It is best to prune these trees during the winter months because it doesn’t affect fruiting that occurs in the spring and it allows the tree to seal up the wound quickly in the spring when growth resumes. It is also easier to see areas that need to be pruned in the winter months. You can see where branches are crossing or rubbing and where the branches are too dense. In addition, pruning in the late winter helps reduce the transmission of different diseases that aren’t active. However, it is best to avoid pruning maple, willow, poplar, birch, hackberry, Kentucky coffeetree, black walnut, honeylocust, and elm due to the high sap flow they have in the spring. Freshly cut wounds this time of year will cause the tree to “bleed” or have excessive sap flow out of the wounds. They are best pruned in the late summer to early fall to avoid sap flow.

Don’t uncover perennials yet. It is still winter, for a few more weeks. Many of our perennials are getting confused with the weather lately and some are starting to green up already. Tulips, Iris, and peonies are starting to emerge and crocus are blooming already. However, if you pull the winter mulch back from these plants or remove the plant material that was left on the plants through the winter, you will be exposing the plant to cold temperatures and removing its protection. The plant will have better survival and less winterkill if you leave them covered through the winter months.

Plan your gardens for the spring. Late winter is a great time to plan what you will plant in your vegetable gardens so you can format your plan to know what you have space for and to ensure that you move your crops around from year to year. This will also help you decide what seeds to start indoors. Mid-February through March is a good time to start the seeds of your chosen warm season crops indoors. Make sure that you have them in a warm location with 14-16 hours of light on them everyday.

crabgrass, Joseph Berger, Bugwood

Crabgrass photo is courtesy of Joseph Berger, Bugwood.org

Don’t use pre-emergent herbicides for crabgrass yet. The soil temperatures have been at an average of 40-45 degrees Fahrenheit over the past 7 days. Even as warm as it has been, crabgrass has not yet begun to germinate. If the temperatures continue at this pace, it will probably germinate early, but we still have a couple of weeks before we need to get the pre-emergent herbicides on. Remember, crabgrass germinates at 55-60 degree soil temperatures, so we still have a bit of warming up to do.