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Ron Smith answers reader's questions about the world of plants and gardening.

By Ron Smith, Horticulturist

NDSU Extension Service

Q: I have a honeysuckle vine growing on a fence that I need to move. When and how is the best way to move it? (e-mail reference)

A: Move the vine in late fall or early spring.

Q: I have what I believe is nigra arborvitae as a natural fence around my home. A neighbor told me that it's too bad that arborvitae dies after 20 or so years. Is this true? (Bellingham, Wash.)

A: That might be wishful thinking on your neighbor's part, so keep an eye on him! There are many arborvitaes that are more than 50 years old in my old neighborhood where I grew up. I can tell you the plants received no special treatment in Buffalo, N.Y., which is famous for its winters and other irrational, unpredictable weather.

Q: I am just like most of your e-mailers who have a plant that won't bloom. My plant has grown twice in size since I bought it and is very green. From what I've read, I don't think mine is getting enough humidity. Our house is kept as dry as possible because we don't like it damp. We live in South Carolina, where the humidity usually is high. What should I do? Would misting be a good answer? If so, how often should we mist? (e-mail reference)

A: High humidity in stagnant air usually leads to poor-looking plants. High humidity with air circulation usually improves the situation. You can set your plant in a tray of pebbles covered with water to get the humidity near the plant higher without affecting the rest of the house. Misting with distilled water also would help, but you must be consistent.

Q: I live in Fargo and have some peonies that are starting to bloom after three seasons. Unfortunately, I planted them along the lake and now we need to do some reconstructive work along the shore. I can't wait on the shore work until fall. My choices are to replant the peonies in the middle of the summer and hope for the best or let them die under the wheels of a Bobcat and a pile of rocks. Any recommendations on how I can increase the slim chances that my peonies will survive the transplant? (e-mail reference)

A: Certainly take the chance on moving them. Cut off all the flowers and withhold watering for a day or two before digging and moving the plants. Dig out as much of the rootball as you can and replant as soon as possible. Give the plants plenty of water. If possible, build a shade tent over the plants to help cut down on moisture loss during hot, sunny days.

Q: I've been looking at your Web page and you appear to be very knowledgeable about birch trees. We have a river birch that has a sticky substance on the leaves. The sticky stuff is falling on other plants and walkways. This has been going on for about three weeks. Do you have any suggestions? (e-mail reference)

A: The sticky substance you reference is either aphid or spider mite poop. Get the tree sprayed with Sevin insecticide or get a systemic, such as the product that Bayer is selling called Bayer Advanced Tree and Shrub Insecticide.

Q: I found your Web site while searching for answers to ficus problems. I hope you can help because I'm afraid my tree is about to die. It's a ficus benjamina corkscrew and is rather large. I purchased it at a reputable nursery in January. When I brought it home, it kept losing leaves. Our house is fairly cool (mid-60s) and the plant is in a drafty location, so I put a humidifier under it and ran it almost nonstop. I also misted it with water almost every day. It seemed to improve and I thought I was out of the woods. About two months ago, I noticed that there were tiny, white bugs crawling all over the top of the soil. The nursery told me they were blind mealy bugs and sold me Safer to get rid of them. They told me that I should apply the Safer only on top of the soil after watering because there were no signs of bugs on the leaves. They said it might take two to three applications to get rid of the bugs. However, I still have the bugs. In addition, about two weeks ago, lots of little brown centipedes came out of the soil after I watered. The tree seems to be drooping, losing lots of leaves and the center of the plant seems dead. I pruned away the dead interior branches and shaped a few of the healthy ones. The runoff water is dirty and filmy and the top of the soil looks white. Is there anything I can do to save the tree? Thanks for any advice you can give. (e-mail reference)

A: Drag the plant outside and dump the contaminated soil. Wash the container with soapy water and rinse well. Wash all the soil off the roots and replace the soil with pasteurized or sterile potting soil. Keep it outside for the rest of the summer in dappled shade. Monitor the plant for any insects that may be considering residency. Most likely, the tree was planted in a nonsterile or nonpasteurized media, which caused all the insect problems.

Q: We just moved to the outskirts of Omaha, Neb. We planted about 60 bushes, a garden and 15 fruit trees. It probably was not a smart idea doing so much planting the first year, but everything is growing well. The hydrangeas flowered for a few days, but then all the flowers and leaves dropped off. Then they sprouted new leaves and flowers for a day or two, but now those have died. The plants look like they're ready for winter, but it's only June. Have we lost them or is there a chance they may come back? What would be the ideal place to plant hydrangeas? Right now they get about five to six hours of sun. We have clay soil, but did put them in a big hole with better soil around it. What about the amount of water they like? We also have other problems. Our burning bushes look OK, but a lot of the leaves have fallen off. The rose bushes look great, but the flowers we've had seem to open, look wilted and die in a 24-hour period. Are they getting too much water? (e-mail reference)

A: I am at a loss as to why your hydrangeas are not performing up to par! Generally, these are one of the easiest flowering shrubs to grow and reward the owner by having big, beautiful blooms. During the first year, keep the soil moist to prevent wilting. Once established, hydrangeas are almost indestructible! Check the stems to see if the cambial tissue is still green beneath the bark. Scrape it with a pocket knife or your thumbnail. If green, there's a good chance they will come back. As far as the site goes, it sounds about right. The burning bush probably is going through transplant/new environment shock, but should recover. The roses may be getting hit by a fungal disease, such as Botrytis, because your description closely matches the symptoms. Correct the problem by not doing overhead watering and pruning out excessive branches to improve air circulation. Do not overfertilize. If the roses are surrounded by ground cover, remove it. Pick up and dispose of all fallen leaves and spent flower buds to prevent reinfection.

Q: I found your address on the Web. Can you tell me the probability of bringing back a wild rose bush? I found a rose bush growing in an area with very poor lighting and a lot of overgrown weeds and trees. I moved it last year to our garden. It has healthy leaves and stems, but has shown no signs of producing flowers. (Kalamazoo, Mich.)

A: Many times wild roses are so vigorous in producing vegetation that they fail to flower during the normal growing season. If they do, it is very sparse or of little notice. Because it is in your garden, it probably is in good soil that receives regular fertilizing. If you can back off on that somewhat, it may come around to producing flowers.

Q: We have a chance to buy a couple of red maples, but the leaves are green. Are they really red maples? If so, will the leaves eventually turn red? (e-mail reference)

A: The red maple species, Acer rubrum, will have green leaves during the summer, but have outstanding red coloration in the fall.

Q: After a 10-year battle, my Canadian cherry finally lost its fight with black knot. I had it professionally removed last week. I am tempted to replace it with another Canadian cherry, but realize there is a significant risk of disease. If the old tree was removed and the stump ground up, is there a risk the ground will recontaminate the tree or is this an air-borne pathogen? There are no other Canadian cherries as far as the eye can see, so I don't know how the tree got it in the first place. It did take a long time before it became diseased. I've considered pursuing alternative cherry trees, such as the Merlot, which is a recent, sturdier cultivar, but is not available in multistem. Are there disease-resistant red cherries or is this a lost cause? (e-mail reference)

A: It's a shame you lost such a beautiful tree. However, you have become a conditioned warrior in the battle against the black knot disease, so I encourage you to follow your dream and get another one. This time, follow preventative maintenance by spraying the new plant with lime-sulfur every spring while the tree is dormant. Spray the tree again when it is in full bloom with a fungicide containing thiophanate-methyl (Topsin, Fungo or Cavalier) as the active ingredient. Be sure to spray while the bees are not active. Read the label to make sure the formulation is cleared for chokecherries. Repeat the spray again 10 days after petal drop. This fungus is spread by rain splash, wind, insects, birds and humans. The fact that you have no visible chokecherries in the surrounding area shifts the statistical advantage for not getting the disease again in your favor, but maintain good vigilance. The problem typically has been overplanting of this particular species because of its beautiful spring flowers and the fruit that is relished by wildlife and jelly and wine makers. Another problem is that people wait until the disease has gotten out of hand to do something. People tend to plant a tree, water it and, if it appears to be doing all right, pretty much ignore it until the symptoms become almost overwhelmingly obvious. Then it becomes a fire alarm to try to save the tree. Go for it and good luck!

Q: I have an apple tree that I planted three or four years ago. Last year it was full of apples containing one or two small, white dots and a brown point in the middle, which looked like an entrance for a small worm. None of the apples were good. There are fewer apples this year and I noticed that they are oily on the surface and definitely not healthy. I pruned the tree in the spring in the belief that it grew too fast. Could you give me any hint about what is wrong with it and what I can do? (e-mail reference)

A: Apple trees often are a high-maintenance item. They need dormant spraying with lime- sulfur followed up by a general orchard spray that is a combination insecticide/fungicide (an Ortho product) when the tree is in full bloom, but not while the bees are active. The trees need to be sprayed again about 10 days after petal drop. Pruning should be done on an annual basis so that too much is not removed at one time. Fast or excessive growth is often the result of overpruning. Avoid fertilization with a high-nitrogen material. If the need is there for fertilization because a soil test indicates deficiencies, use a basic 5-10-5 or 10-10-10 fertilizer or go by the soil test recommendations.

Q: I have a Santa Rosa plum tree. This is the first year it's producing fruit. The fruit is tiny, about the size of a golf ball. It's delicious, but so small! Why is that? Also, the small, ripe fruit is falling off the tree. The other day I saw a squirrel sitting on the fence right next to the tree. I think the squirrels are eating my plums! (Long Beach, Calif.)

A: The small size is likely due to the heavy fruit set. To get larger, but fewer plums, do some hand picking early in the season to lighten the load somewhat. Do this just after the fruit has set. This allows more carbohydrate energy to go into the remaining fruits, which gives you (squirrels, too!) something larger to sink your teeth into.

Q: I laid down sod a year ago. I think it is Kentucky blue grass. I cut it once a week. However, the grass doesn't seem to grow very rapidly even though there has been sufficient rainfall. What is the problem and what is your suggestion? (e-mail reference)

A: There are several possibilities. The grass is not fertilized or the nitrogen level is too low. The soil may be too compacted or there is excessive thatch. It could be a characteristic of the cultivar you used or a there was a natural slowdown after seed head formation. I would start by giving the lawn a light application of fertilizer. We do this on our football fields around the end of June to kick up vegetative growth somewhat. If you have a difficult time driving a spade into the lawn, then it could stand aeration. If the lawn seems spongy, then check for thatch accumulation. About a half-inch is normal or something to shoot for. Too little or anything significantly more than that indicates a problem. Another possibility is the excessive use of pesticides.

NDSU Agriculture Communication

Source:Ron Smith, (701) 231-8161,
Editor:Rich Mattern, (701) 231-6136,
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