This is the Q&A for the Yard and Garden show for May 25, 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: Sarah Browning, Lancaster County Extension Educator
1.The first caller of the show has ant hills throughout her lawn. Is that a good thing or a bad thing?
A. Ants are a beneficial insect, they are predators feeding on many small insects. If they are not in the way of your daily activities, I would leave them alone. However, if they are a detriment to your outdoor activities, you can sprinkle sevin dust in the hole or spray it on the mound.
2. What can be done to discourage barn swallows from making nests on beams under a porch?
A. The best would be to use a porcupine wire attached to the top of the beams or some type of netting to deter the birds from starting the nest there. Once the nest is completed, it cannot be removed due to the eggs in the nest. So be sure to deter the birds before they complete their nests. For more on this, here is a video on Barn Swallows from Dennis Ferraro from Backyard Farmer.
3. A caller wants to know if they can prune the low branches of their river birch now?
A. Yes, it can be done now. River birch trees have a heavy sap flow in the early spring, so waiting until now would cause a reduced amount of sap flow from that tree when it is pruned. Do not remove these branches if it removes more than 1/3 of the tree with these lower branches. That will remove too much of the photosynthetic area in one cutting, stressing the tree too much. Also, do not remove these branches if they are 1/2 the size of the main trunk or larger. It is hard for a tree to seal up the wound from such a large cut.
4. This caller has a small orchard and wants to know how much of the orchard fruit tree he should be spraying on each of his trees?
A. You need to spray the trees enough to get good coverage on all of the leaves. They need to be sprayed thoroughly so that the branches as well as the tops and bottoms of the leaves have been sprayed to hit all the areas where the insects can be found.
5. This caller wants to know when the best time to move peonies is?
A. The general rule of thumb is: ‘if it is a spring blooming shrub, move it in the fall. If it is a fall blooming shrub, move it in the spring’. Peonies are best moved in the first part of September to allow the roots to build in cooler weather. However, they would be fine moved in the spring as well. They may not bloom for a year after transplanting.
This caller also wanted to know if they can divide lilacs and snowball bush and when that should be done?
A. You can divide these, but make sure you take a good part of the roots with. Lilacs don’t divide well, it would be better to layer them and then move that new part. Layering is when you take a branch and stake it down into the ground, while it is still attached to the main plant. This will allow that branch to make roots. Once the roots are present, the branch can be cut from the main plant and transplanted. These 2 plants would best be moved in the fall.
6. A caller has a south facing, full sun, sloped location in his yard. What would be a good groundcover for this area to replace the turf to avoid mowing on the high slope and would require minimal care?
A. Buffalograss would be a good choice for full sun, hot location. Once buffalograss is established it takes very little maintenance. It will take a couple of years of management to control the weeds and to get it established, but it wouldn’t need to be mowed often. Other choices would include a low growing juniper or cotoneaster to cover the ground but have limited management. You could also plant a selection of different full sun perennials and shrubs to cover the ground as well.
7. Are butterfly bushes easy to grow here?
A. Yes, they grow well in Nebraska. Make sure you wait to prune them in the spring after growth begins again. This will tell you how far back you need to prune the canes to get back to where the growth shows up. In hard winters where the temperature fluctuates, they can have winter die back, but otherwise they do fine.
8. A person brought in a picture of a plant they wanted identified, wanted to know how to prune it and if they can cut out the dead stems in it right now?
A. The picture was of a trumpet vine. It is best if it is pruned in the fall or during the dormant season. You can remove the dead branches in the plant anytime. Trumpet vine is an aggressive plant that can spread through the landscape quickly, watch for suckers and cut those out as they grow. Do not spray the suckers as they are growing from the main plant and that could kill the plant too. It also grows very fast and may need to be lightly pruned throughout the growing season to keep the shape and size how you want it.
9. How do you control bagworms on cedar trees?
A. Bagworms should be controlled within a couple of weeks after emergence until the bags are up to 1 inch in length. You can put masking tape inside-out around a branch to collect them as they emerge. Once you start finding caterpillars on the tape wait a week or two before spraying to ensure all the larvae have emerged. This will make one application enough for all the larvae. Bt products, such as Thuricide or Dipel would be best because they won’t harm any pollinators or predatory insects on the trees. Tempo, sevin, eight, or bifenthrin will also work for bagworms.
10. This caller wants to know what to do to prevent seed stalks from forming in rhubarb?
A. Rhubarb will form seed stalks due to many different environmental conditions including cool nights and hot days. Some varieties are just more prone to producing seed stalks early. Just remove those seed stalks as they form and continue to harvest the rhubarb as long as the stalks are still wide.
11. The last caller of the day has a privet hedge along an alley that is not leafing out. It was fine last fall and another hedge in a different location is fine. What is wrong with these privets?
A. This could be due to winter damage and they might come out of it yet. Look at the base of the plants, it could be due to rabbit or vole damage through the winter. If it is that, the privets may not come back. Because this is a full hedge along the alley and they are all looking the same, this could be due to herbicide damage. If someone sprayed the alley to control weeds, they may have sprayed something that got into the roots of the privet and killed them.
This caller also has a row of Rose of Sharon not leafing out either. What is causing that?
A. This could also be due to the same herbicide from the alley. If the herbicide was something like tordon or triclopyr, it would be very mobile in the soil and could have damaged the Rose of Sharon as well.
This caller had a final question that she received hemlock via delivery while the ground was still frozen. The hemlock trees were kept in the garage until the weather warmed up a bit but now have no green needles left on them. Will the trees survive?
A. If there are no green needles or very few, the trees will die. Evergreens need some green needles to continue to grow. It would be best to purchase trees from a local nursery that were grown locally. They are more adjusted to our environment if they are grown locally. Also, if you purchase locally, you can purchase when you are ready to plant and not have to store it until the weather is right. In addition, it might be better to choose a different plant species, hemlocks don’t do well in our environment. It might be best to choose a columnar juniper like a Taylor Juniper or something else better suited to our clay soils and high humidity in the summer.