Problems in our Gardens

Vegetable garden 1

Growing my own produce in my backyard is one of my favorite things of summer! Vegetable gardens are great exercise, give you an excuse to eat healthier, and are very enjoyable but they can be a lot of work as well. There are always problems in our vegetable gardens, usually they are temporary or easily fixed.

Production Issues

The weather this year has not been favorable to our plants. We have been facing aborting flowers of our plants due to heat and low pollination. Now, even though our plants are producing, the tomatoes are not ripening up. The hot weather contributes to this as well. When temperatures are consistently as hot as they have been lately, tomatoes may develop but they don’t turn red. According to Purdue University, the pigments responsible for the red color in our tomatoes are not produced when the temperatures exceed 85 degrees. So, when we see long stretches of very hot weather, our tomatoes will not ripen. Be patient, they will ripen eventually when the very hot temperatures recede.

Blossom end rot is also starting to show up in our gardens. Blossom end rot is when the blossom end (the end not attached to the plant) begins to rot. This is due to uneven watering, which is seen quite often in the early part of the growing season where we see stretches of drought surrounded by 2-3 inch rains. Again, this should fade through the season as the plants grow through it. You can still eat the other end of the tomato and discard the rotted end or give your plants time, the next harvest should be better.

Cracks may also start to appear in our tomatoes due to the weather. With uneven watering comes cracks in our developing fruits. Our fruits can grow rapidly due to rapid intake of water which can build up pressure in developing tomatoes. Cracks typically appear on the top of the tomato, often in rings, and are not harmful to us if we eat them. Check for insects that may have gotten into the cracks of our fruits before eating.

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Grass clippings are applied as mulch around zucchini and cucumbers

Using Mulch

Mulch is a great way to combat these issues. Many of our problems in our gardens stem from uneven watering or plants that got too hot and dry to deal with the stresses of the environment. Mulch can keep moisture around the plants and keep the roots cooler to help with these issues as well as reduce competition from weeds. Grass clippings make a great mulch. If the grass has been treated with any herbicides this season, look at the label to know if or when it can be used as a mulch. Grass clippings break down quickly so they should be reapplied often. Straw is also a great mulch for the garden and it wouldn’t need to be reapplied as often. These types of mulch can then be tilled into your garden at the end of the season or before next season to add nutrients back into your soil.

squash vine borer damagePests

Squash bugs and squash vine borer are seen in our gardens every year. Squash bugs cause yellow speckling on the leaves and feeding damage on the fruits. You may also see rusty colored eggs on the underside of the leaves that can be removed and destroyed. Squash Vine Borer causes rapid death and wilting of the plants. These pests feed on plants in the cucurbit family, which includes zucchini, squash, cantaloupe, watermelon, cucumbers, pumpkins, gourds, etc. Squash vine borer can be controlled by wrapping the stem of your plants with aluminum foil to stop the females from laying their eggs on your plants. Other controls include Carbaryl (Sevin), Permethrin (Eight), or bifenthrin (Bifen). This will need to be reapplied often through the growing season. It is best to switch between at least two of these products to avoid resistance from developing.  Always follow the label recommended rates and follow the pre-harvest interval listed on the label when harvesting fruits and vegetables after using chemicals.  Spray the undersides of the leaves and the base of the plant thoroughly.  All sprays should be done later in the evening to avoid damage to bees and other pollinators.

Yard and Garden: May 11, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for May 11, 2018. 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 August 3, 2018. 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: Dr. Paul Read, Professor of Viticulture, UNL

1.The first caller of the show has asparagus beetles. How can they be controlled?

A. Use a dust or spray formulation of Sevin to control the beetles. When using chemicals around vegetable or fruit crops, be sure to pay attention to the PHI listed on the chemical label. The PHI is the Pre-Harvest Interval which indicates how much time must pass between the application and harvest to avoid pesticide residues. You can also hand remove the insects, destroy them in a bucket of soapy water after removal. The asparagus beetle should be controlled because they will lay their eggs on the asparagus as it grows which can reduce the saleability. Also, their feeding can reduce the amount of ferns produced which can weaken the plant.

2. A caller has a Bing cherry tree that has been planted in the landscape for a few years and it is not growing and seems to be dying. What is wrong?

A. Sweet cherries, including Bing Cherries, do not grow well in Nebraska weather. For cherries in Nebraska, tart cherries will grow here and do best.

3. This caller has grapes that are not taking off that are in their second year of growth since planting. He has 2 varieties, but not sure which varieties they are. What should be done to get them growing better?

A. Grapes are self-pollinated, so only one variety is necessary. It would really depend on what varieties this caller is growing to know for sure what is wrong with them. They may not be the best choices of varieties for this area. For a listing of good varieties to choose from, visit the UNL Viticulture Program website. For good general care: the plants should be trellised and will be productive by the 3rd year. Water is very important for establishment in the first year. It would be beneficial to mound the soil around the base of the plant during the winter to work as insulation.

He also wanted to know if he could move strawberries into an old baby pool? Would this be enough space for the plants to grow?

A. They would be best grown in the ground, but could live in a baby pool as long as there are drainage holes in the bottom of the pool so the soil doesn’t get saturated.

blossom end rot zucchini
Blossom End Rot on Zucchini

4. How do you deal with blossom end rot in vegetable gardens?

A. Blossom end rot is due to uneven watering. It is technically a calcium deficiency, but the calcium is there it’s just not available to the plant due to the water issues. Even watering is going to be key, it is just hard to do in Nebraska when we face drought periods in between heavy rains. It is just best to water the plants 1 inch of water per week over the week to ensure even, adequate watering. Typically, when we see blossom end rot, we only see it for a couple of weeks early in the season, it is not usually a season-long condition.

5. A caller wants to control the dandelions in her lawn and also reseed. How can she do this safely?

A. We are really ending the window of opportunity for reseeding a lawn this year. It is difficult to get turf established when temperatures start to rise in May. Dandelions are best controlled in the fall with a broadleaf herbicide. At this point, the timing for both control of the dandelions and overseeding the lawn would be around the same time. However, you should not overseed the lawn and use herbicides at the same time or the herbicides could injure the turf seedlings. Tenacity, or a product containing Mesotrione can be used at seeding to control broadleaf weeds and not injure the grass seedlings. I would advise using this tactic in the fall or to overseed in late August to mid-September and allow the grass to grow enough to be mowed 3 times and then use a late fall application of a 2,4-D product to kill the dandelions. If there is time for a second application of the 2,4-D at least 2 weeks after the first application and into the early part of November, that would be most beneficial.

6. This caller has plum trees and elm trees growing in their peonies. What can be used to stop the regrowth of these weedy trees without harming the peonies?

A. The safest option would be to cut the trees off then paint glyphosate (Roundup) on the cut stumps shortly after pruning. Be careful to not get the glyphosate on the peonies to avoid damage to them. I would advise against using 2,4-D in this situation to avoid volatization of 2,4-D and causing problems to the peonies.

This caller also wanted to know if she can use Grass-B-Gon products in the peonies and iris’ to control grasses growing in the plants?

A. Yes, this is labeled for use in broadleaf plants to kill grasses.

7. A caller wants to know what she can use for weeds in the asparagus patch?

A. mulch is going to be the best option for any type of weeds in asparagus. Our herbicides are not labeled for use in this vegetable crop. After she is done harvesting the asparagus for the year, she can cut it back so all green growth is below ground and glyphosate (Roundup) can be used over the bed. This could be used in the fall after the season, followed by mulching the plants in to reduce new growth.

8. This caller has a disease on his pine trees. Is it too late to spray the trees to prevent the disease?

A. This is likely either needle blight or tip blight. The timing for spraying for needle blight is in mid May as the needles are emerging, with a second application in mid to late June, so it would be the correct time to spray for this disease. If the disease is the tip blight, the timing for spraying for that is in the third week of April, just before the needles emerge with a second application 7-14 days later. You would be past the prime window for this disease, but it would still be beneficial this early to treat for this disease as well to avoid too much spread of the disease. With the spring as cool as it has been this year, most things are pushed back a bit and fungicides would still be beneficial for these trees.

9. A caller asked why tordon could not be used for the weedy trees in the peonies that caller #6 asked about?

A. Tordon will kill the peonies as well. Tordon is a mobile chemical that can get from the roots of these trees and into the roots of the peonies, killing them as well. Also, Tordon is not labeled for use in a landscape setting, it is only labeled for roadsides and ditches.

10. This caller has 2 viburnums that are growing in her yard. One has leafed out fine but the other leafed out only part of the way and has now stopped emerging from winter dormancy. Will it be ok?

A. Don’t give up on the plants too soon this year. The spring has been quite cold and unusual for our plants. The general recommendation is to wait until June 1st before determining death in the plants. Because it started growing, it is likely that it will be fine. Make sure that the plant is getting plenty of water to help it pull through. If the plant begins to sucker from the base, this could be a sign that the top had cold damage.

11. A caller has 2 ornamental grasses that haven’t greened up yet. Will they survive or are they dead?

A. Just like with the viburnums, give the plants time to come out of their winter dormancy. Many of the ornamental grasses have not begun to green up this year yet. Wait until June 1st before deciding to destroy the plants that may just be slow to come out of dormancy this year.

12. This caller’s lawn is brown and pulls up with no roots attached. Could it be grubs?

A. If there are no roots attached to the grass, it is most likely due to grubs. Grubs can be managed with a grub control product applied to the grass in mid-June. For the grass that died, you can overseed the area in late August to early September.

13. A caller has a patch of rhubarb that is not growing much and is going to seed early. What can be done about that?

A. Rhubarb will start sending out seed-stalks in warmer weather. Some varieties, though, are more prone to send out seedheads early in the season. Cut off the seedheads as you see them start to form to push energy back into the roots and leaf production rather than into seed production for the plants.

This caller also wanted to know if you can root lilacs from a cut branch?

Lilacs are difficult to get to root. The best chances to get it to grow would be to take a piece from the base of the plants that has roots attached to it already. Divide the plant by taking a section off the side of the plant would be best.

14. What would be a good choice for an organic weed killer for dandelions?

A. If the population is manageable, hand removal would be the best organic choice. There are other products such as corn gluten meal and dried distillers grains which are used for pre-emergence weed control. According to the University of Minnesota, ‘It should be noted that any claimed herbicidal effects of Dried Distillers Grains have not been proven or verified as they have been for corn gluten meal’. For post-emergent organic weed control, vinegar can be used, but it is non-selective so it needs to be used as a spot spray. It is important to remember, that bees love dandelions and a small population can be tolerated and helpful for our pollinators.

15. The final caller of the day wants to know about mulching her garden. She uses straw but wheat comes with the straw mulch. What can she do?

A. Straw mulch can bring weed seeds with it, but it does make a great mulch for a vegetable garden. It would be best to shake the straw out over a tarp before applying it to the garden to pull most seeds out of it. Also, using older straw would help so that the seeds would have all germinated before use. Grass clippings make another great garden mulch. Just make sure that the grass was not treated with a pesticide before applying it to the garden. The pesticide label will tell you if or when those grass clippings can be used on a garden again this year. Grass clippings do break down quickly, so it is best to reapply this mulch often or the weeds will poke through.

Yard and Garden: March 30, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for March 30, 2018. 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 August 3, 2018. 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: Justin Evertson, Green Infrastructure Coordinator, Nebraska Forest Service

1.The first caller of the year has brown rot in her apricot and cherry trees. How can this be managed this spring?

A. Brown rot is a fungus that affects the fruit of stone fruit trees. Spraying with Captan or Chlorothalonil products or using an Orchard Fruit Tree Spray throughout the growing season will reduce the disease. Avoid spraying during bloom if using a combination spray that contains an insecticide to avoid damage to pollinating insects. For more information on spraying and timing, visit food.unl.edu/local-food-production and click on ‘Managing Pests in Home Fruit Plantings

2. A caller has been advised to use a type of fescue called ‘Water Saver Fescue’ because it is more drought tolerant. Would this be a good turf choice?

A. This variety is a turf-type tall fescue variety that is an RTF variety. The RTF is a new type of tall fescue that forms rhizomes, allowing it to fill in a yard rather than just form clumps like the traditional tall fescue. Turf-type tall fescues are preferred to other types of grasses because they do well in our environment and are more drought tolerant than other turf species, such as Kentucky Bluegrass. This wouldn’t be any more drought tolerant than any other turf-type tall fescue species, but it would be drought tolerant.

3. When should a person fertilize their lawn?

A. If using the maximum fertilizer applications for a year, we recommend fertilizing with the holidays: Arbor Day, Memorial Day, Labor Day, and Halloween. It is not necessary to do all of these fertilizer applications. If you leave the grass clippings on your lawn, that replaces one fertilizer application over the course of a growing season. If you only apply fertilizer one time per  year, the best time is at Halloween. If you would like to apply 2 applications per year, the other time would be to add an application on Arbor Day.

4. This caller wants to know what is best to use in a vegetable garden to keep the weeds down?

A. In a home vegetable garden, mulch is going to be best for weed control. There are a lot of mulch products that can be used in the garden to reduce weeds including: wood chips, grass clippings (that have not been treated with any pesticides), newspaper, leaves, and cardboard.

green-asparagus-pixabay5. A caller wants to plant a new asparagus bed. How should she go about planting and caring for her asparagus?

A. Asparagus is a great plant for a home garden. Many people want to get plant starts from a neighbor to start their patch, but it is best to just purchase a new set of crowns. When planting asparagus crowns, dig a trench 8-12 inches deep and bury the crowns only under 2 inches of soil. As the plants poke up through the soil, add more soil until the soil is level. Avoid harvesting asparagus until the third season of growth to allow the crowns enough time for root production. For weed control, mulch is best, the same mulches used on a vegetable garden work great for asparagus beds. Preen that is labeled for use around asparagus can be used in the spring to prevent annual weeds from germinating. In late May to early June, when finished harvesting asparagus for the year, you can break all the spears off below ground, leaving no green growth above ground, and spray glyphosate over the bed to reduce weeds.

6. This caller has Colorado Spruce trees with needles at the bottom of the tree that are turning brown. What is wrong with the tree and how can it be fixed?

A. This is likely due to needle cast disease. You can spray the tree for needle cast in May using a liquid copper fungicide. For more information, view this Nebraska Forest Service publication on Diseases of Evergreen Trees.

7. When is a good time to transplant Iris and Peonies?

A. The best time is in the fall, but it can be done now. They may not bloom this spring if you move them now, but will bloom again next year. Be sure to get the peony planted at the same depth it is now or it won’t bloom.

8. A caller has a vine growing on the trees they thought was poison oak. How can it be controlled?

A. It is likely that this is woodbine or Virginia creeper. It doesn’t all have to be killed off, it makes a great groundcover. Cut off the parts growing up the tree and leave the rest for a groundcover. If you need to manage it cut it off and treat with glyphosate or triclopyr or just hand pull.

9. The final caller of the day has recently read that trees can “communicate” to other trees if they are attacked by a pest to help the other tree prepare to defend themselves from the pest problem. Is there any research on this?

A. There is a theory that trees communicate. A German Forester is looking into this idea further. Here is the Article from the Smithsonian Magazine regarding this topic and the research on how trees communicate.