NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665
November 4, 1999
Ron Smith, Extension Horticulturist
North Dakota State University
Q: I think my lawn is plagued by ground ivy, but I also need to know how to get rid of it.
I also have some plant that has bluish purple star-shaped flowers that I would like to get
rid of.
Is crabgrass best treated with spray or pellet chemical treatment, and is fall the best time for treatment? (e-mail)
A: Ground ivy will take a couple of applications of Trimec to control it. The same chemical will also take care of the violets -- the purple flowers.
Crabgrass should be dead now from the frosts. Being an annual, it is best controlled by a pre-emergent herbicide in the early spring.
Q: Can a person put crabgrass preventer on in the spring over a piece of ground that has been sown with grass? Also, can I spray Roundup over tulips and lilies that are not up so I can kill quackgrass? (e-mail)
A: There is only one pre-emergent crabgrass herbicide that can be used that way -- Tupersan (Siduron). All others will take out the desired turfgrass seed as well. Roundup is deactivated as soon as it hits the soil. As long as there is not green showing above ground, the tulips will be safe.
Q: I'm looking for a phone number and address for T & T Seed Co. We sold garden seeds from them when I was in FFA. They were located somewhere in North Dakota. Can you help me? (Chester, S.D.)
A: I did a state-wide directory search and came up with nothing. I think they originated in Canada and had opened a branch in Minot, but that was several years ago. No such place exists now. Sorry!
Q: Can you tell me why my tree, a house plant, is dropping its leaves? (Parshall, N.D.)
A: Leaf drop with many houseplant species is directly related to a change in environment -- a reduction in light, alteration of watering regime, temperature shifts, radical changes in humidity. If you have moved it recently, from one room to another, or to a new location in the same room, that would be enough to initiate leaf drop. After a period of four to six weeks the tree should stabilize, with a little to no further leaf drop.
Q: Can you tell me what is wrong with my evergreen needles? Do they have spider mites, or why do they turn brown and fall off when it gets warm or hot out? (Scranton, N.D.)
A: The needles showed no disease symptoms -- just normal senescence. This occurs every autumn with the oldest needles on the interior of the tree. You have nothing to worry about unless the action is becoming wholesale on the tree, involving the current season's growth.
Q: I have been wondering whether you planted sweet potatoes and if so what were your results. After your columns about sweet potatoes many people here tried them and reported that they had good results but that the potatoes got so large. I planted 14 plants and got 57 pounds. I know Gurney's Seed & Nursery is pleased with you as they sold a lot of plants to this area.
I also read that your radishes do not produce seed. I had some blooming at the time so I left them in the garden to see what they would do. They produced seed and for the past three weeks we have been harvesting the most wonderful radishes that have grown from the seeds. They are much better than spring radishes as the cool weather agrees with them.
As you can see, I like a gardening challenge. I am trying northern hardy peach trees at the present time. I will protect them like I do my roses. I hope to let you know in a couple of years that I have wonderful peaches. (e-mail)
A: Well, I'm glad to hear that everyone's sweet potatoes did so well. Mine produced lots of vine and enough sweet potato meat for one meal -- that's it! Of course they were under water for days a couple of times. This doesn't help crop production much!
Good luck with your peach experiment. I tried and failed -- the deer ate the whole two trees!
Q: I have a bur oak that I picked up in Bemidji, Minn., about 12 years ago. This fall after the leaves fell, I noticed grape sized brown clusters (with an exit hole in each?) on a few of the branches. I am wondering if this is a concern and how to treat? (Jamestown, N.D., e-mail)
A: Thanks for the good description. Not a concern. This is one of the many galls that affect oak trees. They come and go, and are caused by mites or small wasps. Control is not necessary, and attempts are usually ineffective anyway. If their presence bothers you, I suggest pruning the clusters off early next spring before new growth begins.
Q: I am following all of the directions I have heard of for caring for my hibiscus, except the leaves are turning yellow. Is this due to the soil it was originally planted in? (Wahpeton, N.D.)
A: It could be your soil is deficient in one of the chlorophyl-forming nutrients. Give it a shot of houseplant fertilizer once a month to see if that improves the appearance.
Q: I have a couple of lilac bushes, and when spring comes around I only get a few lilac flowers on bushes. How can I get more flower on the bushes? (Minot, N.D.)
A: Lack of flowering of lilacs is usually due to late or early season pruning. If you prune, do so immediately after flowering, as the flower buds on lilacs develop on subsequent new growth. Pruning in August, for example, would remove those newly formed flower buds; pruning in March would also remove them just prior to flowering.
If you don't prune, then the problem could be the location. Lilacs thrive in full sun, and do poorly -- flower-wise -- in shade. Another problem could be borer damage, but there would be evidence of twig death if that was the case.
Q: Help! The tomatoes in our community got sick this year. The tomatoes were half red and half green and spoiled too fast. I am a 93½ year old grandmother and love to garden. (Rolette, N.D.)
A: The likely problem is a combination of factors; first, blossom end rot, followed by late blight fungus taking over. Try a different variety or two next year, plant in another location and hope Mother Nature cooperates with some decent tomato-growing weather!
Q: While visiting my son in southern Minnesota I noticed something strange about his sugar maple. The bark is peeling off in rather small pieces, leaving the tree trunk sort of an orange color. The weather has been really dry this summer in this area. Could this be a factor in the condition? (Breckenridge, Minn.)
A: Bark loss and leaf discoloration during environmental stress is not uncommon. Generally, your son has nothing to worry about, unless of course, the drought continues! Encourage your son to apply ample water to the root system of the tree prior to winter freeze-up. This will help the tree survive the winter and get off to a good start next spring.
Q: Is it better to cut down the perennials in the fall or in the spring? I have always left the ones with seed heads for the birds and to catch the snow and now people are telling me that I am doing it wrong. What is your advice on when to cut? (e-mail)
A: Generally, perennials are left uncut going into the winter. The trapped snow they create acts as extra insulation and provides extra moisture. This is especially important with perennials that may be borderline in hardiness. Those that are "crowbar tough" veterans of the North Dakota climate need not be treated that way and may be cut back now, if one so desires.
It also boils down to a housekeeping preference: do you want a clean, snow-swept landscape for the winter? If so, then cut them back now; if graceful drifts of snow are more suitable to you, then allow the tops to remain.
When in doubt, allow them to remain, and cut them back in the spring!
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Do you have a gardening or houseplant question? Write to Hortiscope, Box 5051, NDSU Extension Service, Fargo, ND 58105 or e-mail to Ron Smith at ronsmith@ndsuext.nodak.edu .
Source: Ron Smith (701) 231-8161
ronsmith@ndsuext.nodak.edu
Editor: Dean Hulse (701) 231-6136