NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665

September 21, 2000

Hortiscope

Ron Smith, Extension Horticulturist
North Dakota State University

Q: I am looking for a juniper that can tolerate alkali soil. I have a compact juniper in this alkali soil that is barely surviving after thraee years. (Carrington, N.D.)

A: Why not try the compact pfitzer juniper? It can grow in anything outside of concrete. They grow 1-2 feet tall. ‘Broadmoor’ juniper is another one to consider, staying even lower. There are dwarf honeysuckles that will also do quite well. ‘Miniglobe’ and ‘Clavey’s’ dwarf are two good examples to consider. While Andorra junipers are nice, they need more refined soil conditions to look decent. Be sure to follow good soil prep procedures before replanting.

Q: I am noticing a problem with a linden tree that the builder installed at the front of the house. I am enclosing a leaf cutting. The tree is approximately 13 feet high now and is planted inside of a built up stone wall. It is approximately 8 feet from the front window of the house and 5 feet from two sides of the stone wall. From what I have read about the size and shape of this tree, it appears to me that this tree is not appropriate as part of the front foundation planting and that it will cause problems in the future. (Somers, N.Y.)

A: Your linden is a cultivar of the littleleaf linden - Tilia cordata - most likely the ‘Greenspire’ which is one of the most common cultivars on the market. This is an excellent shade tree for lawns and other large areas. The problem will likely come not with the roots, but with the tree’s spread. This cultivar can reach 40 feet in 10 years, with a 30 foot spread. The roots are deep, coarse laterals, so they should not exert any lateral pressure as a silver maple or American elm would. These trees do prune beautifully. Europeans often shape them into hedges, so the spread can be easily controlled on your part, if you so choose. If you can, get your contractor to move the tree further into your lawn to compensate for the eventual size. Do this either in the fall or early spring when the tree is leafless (dormant).

Q: Enclosed are some pictures of my cedar trees. The trees are planted in pretty low ground and have tiny bugs eating on them. I was told to use Orthene, but that didn’t do anything. Is there something that I should spray them with? Should I remove the infected trees? I have noticed that the bugs prefer the light green cedars over the dark green. (Winner, S.D.)

A: From studying the photos you enclosed I note the grass and deciduous trees in the area to be either dormant or dead. If the pictures were taken in the spring before leaf-out then that is the reason; if they were taken in the last 4-6 weeks, then the problem is likely a rising water table slowly killing the trees - or a sump area where water collects. The insects are attacking the trees because they (the trees, that is!) are stressed. I would remove the infested trees so the insects don’t have the convenience of simply moving to the healthier ones once they get done with their current victims. Sevin or malathion are better insecticides to use.

Q: Several years ago I purchased a Clematis plant at Walmart. It grows and grows, but does not bloom. Is it possible to get a Clematis that is not for our area? (Grand Forks, N.D.)

A: There are as many Clematis as Smiths! So, yes, it is possible to get a non-adapted Clematis - especially from national chains where purchasing decisions are made in one location for the entire country. I’d suggest looking for a Jackman variety of Clematis. They seem to do best in our area and are looking especially good this year!

Q: I have a miniature rose bush that I received for valentines day. It bloomed beautifully, but the pot seemed rather small so I repotted it in May or June. The leaves are turning yellow now and falling off and it isn’t blooming. I use Miracle Gro in the water that I give it. Also, I have peace lily that I have had for a couple of years. It doesn’t seem to grow much and doesn’t bloom. I also use Miracle Gro on it. I keep them both in a south window with a front porch so they do not get direct sunlight. (LaMoure, N.D.)

A: You are growing two plants with differing light requirements in the same location. The porch is ideal for the Spathiphyllum, while it is inadequate for the rose. Try to gradually move the rose into increasing hours of direct sunlight to see if that doesn’t help the situation. Start with 30-45 minutes the first day and build up from there, until it is getting about six hours. With the lily, just be patient!

Q: I planted my blue spruce Pine trees too close to my house; now I need to move them. My question is how to go about moving them. One tree is 5 feet tall and the other is e feet tall. Is this possible? Everyone is telling me bits and pieces of information of what too do. Do I have to stake them down? Do I wrap them in burlap before replanting? Please Help me!! (E-mail reference, Fair Haven, Mich.)

A: Spruce the size you are referring to are transplanted by the thousands every day in this country. Here's what to do to assure a good chance of survival:

1. water the trees well one day before you want to dig them.
2. dig holes where you want to plant them. Water the holes.
3. with a straight edge shovel, dig a trench around the trees making a "ball" as big as you, or you and someone else, can handle.
4. get a strip of burlap and roll it under the ball of each tree, pulling it up on each side to create a "hammock" to carry the tree in to place it in the new planting hole.
5. set the tree in the hole, burlap and all, and backfill to the same depth the tree was originally planted at
6. give the transplants a shot of Miracle-Gro as you are watering them in.
7. if the trees are located in a wind-prone area, stake them, but for ONLY ONE GROWING SEASON. Too many people leave the staking material on until it girdles the tree, killing or badly disfiguring it.

That is it. They should thrive and do well in their new location. I'd suggest getting on with the transplanting ASAP to give the roots a chance to re-establish in the new location.

Q: I have collected some tulip and seeds from other spring bulbs, and want to plant them. I saw in another question that they should be planted in September. If so, can I expect to see any growth this fall or do they wait until spring? Should I do anything special when planting?

There are many wild rose plants near where I work. If I take some of the seed pods can I just plant the seeds? Do wild roses have any problems being around more cultivated roses?

(E-mail reference, Amherst, N.Y.)

A: Yes to all of your questions, except the last one. Tulip seeds can be planted shallowly this fall, and will germinate the following spring. I would mulch them lightly with peat moss after the soil freezes initially. The same with rose seed. Wild roses will not have any problems with being around domestic ones.

Q: I am having problems with my maple tree in the back yard. The leaves are yellow and have large black spots on them. They fall off all the time as if it is turning fall. I don't know how old the tree is because we just moved into this house this February. I don't know what kind of maple it is either. (E-mail reference)

A: It sounds like your tree has a disease known as tar spot, which is not known to be fatal, just disfiguring. To control, rake all fallen leaves this autumn and dispose. The following spring apply Bordeaux mixture every two to three weeks during leaf emergence.

Q: Can you tell me what to look for when purchasing seed to ensure that it is disease resistant? Also, would it be a good idea to move my garden if I have diseased plants in it now? (Pettibone, N.D.)

A: Generally anything that is tagged with the designation of AAS - All America Selection - is disease resistant. Any that are designated "F₁ Hybrids" are also usually bred for disease resistance. Also, for the letters VFN after the tomato name. That means it is resistant to Verticillium, Fusarium, and nematode damage. Burpee supersteak hybrid is an example.

Actually, moving your garden to a new location will go a long way to limiting disease problems with Glads, tomatoes, potatoes, and cucumbers.

Q: Last year toward the end of the season I had squash beetles, so I removed all the plants and sprayed with Malathion at the end of the season. I then removed all the mulch and sprayed again. This year I noticed that they were back early and I sprayed with Malathion again. How much should I use of the Malathion to a gallon of water and would it be ok to mix it with Sevin as I use Sevin on the rest of my garden? I heard that Sevin will not kill the beetles, but Malathion will. Is this true? (Dimock, S.D.)

A: Try a rotation crop in a different family, like carrots, beets, beans, or tomatoes. Squash beetles are difficult to control. That is why a variety of insecticides should be used. What you are likely experiencing is species resistance to Malathion - the insects are essentially using it as mouthwash. Sevin will work, along with Diazinon, Bioneem (organic approach), insecticidal soap (also organic), and if you really want to give them a dose they won’t forget, use a spray composed of liquified garlic, onion, and habanaro (or jalapeno or cayenne) pepper. Your precaution: wear rubber gloves when preparing and applying. That pepper is hot! Liquify (or finely chop) one clove of garlic, one small onion, and one of the peppers (some use the powdered form). Mix it all with a quart of water, steep for at least an hour, strain thru cheesecloth, and add a tablespoon of liquid dish soap. Mix it well, and apply it when you see the dirty bounders! If they tolerate that, get a white flag and surrender!

Q: When is the best time to transplant rhubarb? I have several red plants, but they only get pencil thin, It that the variety of rhubarb? Also, can I cut back the peonies now or do I wait until it freezes? Can I cut back lilies, iris, and painted daisies now? (Esmond, N.D.)

A: The pencil stalks usually indicate the plant needs to be moved. If you want to assure successful establishment, wait until either this fall or early next spring to transplant. Your peonies and bulb foliage should be kept on until a couple of frosts hit. Removing the foliage now would be like setting you down for a three-course meal, but making you stop after only one course! The plants will weaken and eventually die over the years if this practice is followed.

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: Gary Moran, (701) 231-7865