NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665
May 25, 2000
Ron Smith, Extension Horticulturist
North Dakota State University
Q: I have had my azalea since the first of March, and now it has started losing its blossoms. What do I do with it now to keep it growing? (Valley City, N.D.)
A: You can do either of the following. One, plant it outside on an east or north exposure for the summer, and make sure it is in plenty of sphagnum peat moss and that the soil is kept moist. Or two, continue to keep it as a houseplant, but you will need to fertilize it with acidifying fertilizer. Generally, following the first recommendation gives better results for the plant. In both cases, use liquid fertilizers that are specific for acid-loving plants.
Q: We have several trees around our acreage, from maples to spruce trees. My husband started some plants several months ago from seeds he gathered among our trees, but they seem to be at a standstill. Moss has grown around the soil, and the sprouts look a bit weepy and aren't growing any more. We have them in the south window and covered with a plastic breathable lid. I would like to know what type of tree it may be. The cones are about 3.5 inches long and very puffy, and the width is about 1.5 inches. The sections are very jagged on the tips and sides.(Alberta, Canada, e-mail)
A: From your description, it sounds as if you are attempting to grow some spruce seedlings. I suggest that you get them outdoors after the frost danger has passed. Be sure to provide hardware cloth or something similar around them to protect them from mice, rabbits etc., and be sure to place them in full sunshine.
These plants have what is known as determinate growth. This means that they will put on a flush of growth and stop for the season. The following season they will break dormancy, grow again, and stop at particular point, depending on the conditions they are growing in.
Q: Do you think that I should wait until the blossoms on my pear trees are fully formed to attempt a Q-tip pollination procedure, or will wild bees have visited the blossoms by that time? (e-mail)
A: Very likely, the wild bees will have found your pear blossoms, unless it is too windy or rainy (or both!). You don't want to use a Q-tip either if you try to do some pollinating. A small artist's brush works better to transfer the pollen to the stigma. Just be sure the pollen is mature when attempting to do this, or the results will be nil. Mature pollen will transfer to the brush; immature pollen will not. So, if you are brushing the anther for pollen and nothing is picked up, none will be transferred to the stigma.
Q: A mountain ash tree in my yard recently died. My neighbors tell me that there was a mountain ash in the same spot that died as well. Is there something wrong with the soil in that spot? There is a beautiful mountain ash about 25 feet away that seems to have no trouble. Also, I replaced some dying potentilla shrubs in front of my house, but there is one spot where everything I plant dies. Any solutions? (Cavalier, N.D., e-mail)
A: There must be a toxicant of some kind in the soil that is nailing everything you plant. Could be a pesticide residue or construction debris.
Mountain ash are also a little fickle in my book. They seem to be prone to fireblight and other diseases in some instances. I'm glad that you have one that is performing satisfactorily for you.
Q: Why are my evergreen trees dying? We have already cut down three large ones with the same problem. I know it isn't sunburn because the problem affects the north side of the trees. What can we do? (Maddock, N.D.)
A: If you haven't been using a phenoxy-type herbicide (2,4-D, MCPP, etc.) around these trees, then it must be needle cast--Rhizosphaera kalkhoffii. When the trees are badly infected, your best bet is total removal of that tree.
If the symptoms are just starting on the trees, then spray them with either Bordeaux mixture or Bravo in early June and again in early July. This usually will bring the disease under control.
Q: My asparagus bed (at least 40 years old) is root bound with quack grass, dandelions etc. Are the asparagus roots worth trying to transplant, and is this the time of year for such a project? Or is there a spray that could kill everything but the asparagus? (Jud, N.D.)
A: A 40-year-old asparagus bed has served its duty to humanity. Kill everything off this year and plant something else. If you still want to grow your own asparagus (I don't blame you for wanting to!) get some Jersey Giant crowns next spring and begin anew in a quack-free setting!
Q: I would like your opinion on hedges. I have been considering Amur River North (privit hedge) or caragana. I have looked at Amur maple and dogwood but neither is thick enough. Would you comment on your choice. I want something thick that I can surround a garden with, and perhaps 10 feet tall--max. Like those seen in English-type gardens. (e-mail)
A: The best hedge for thickness and to respond to regular shearing for English garden formality is the cotoneaster. The Amur River North privet is not quite hardy enough for North Dakota, and while the dogwood is a shrub that makes an attractive hedge, I have never seen it respond to formal pruning in an attractive way. Without a doubt the cotoneaster is the right choice.
Q: I just had planted three new maple trees called Autumn Radiance. The trees are about 15 feet tall and 2 to 3 inches around. They are planted about 9 feet away from each other in a row and 6 feet from a wooden deck (looks kind of close). The nursery did not have any pictures of the tree, nor very much information. Could you send me information on the tree, such as shape, recommended planting distance and tips on care? (e-mail)
A: In the book, "Manual of Woody Landscape Plants," Autumn Radiance is listed as a zone 4 plant, having a dense oval form with green summer foliage that turns brilliant orange-red in the fall. The book mentions nothing about the height or width, but knowing the species from when I lived in Ohio, I would suggest doubling the spacing you presently have so they will not be overcrowded as they mature.
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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