NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665
August 26, 1999
Ron Smith, Extension Horticulturist
North Dakota State University
Q: This spring we had trouble with cucumber beetles which we controlled with Sevin, and now we are losing runners with bacterial wilt. Can you give me any suggestions to stop this? Will we have the same problems next year? Will rotating to a new area do the job? Is it OK to eat from the diseased plants since we take our produce to market? (Roseglen, N.D.)
A: If the fruit itself is symptom-free, it should be OK to market. Nothing you can do about the wilt now. Try to avoid overwatering. Next year plant it where you have corn or a Solanum crop (tomatoes, peppers, eggplant, etc.) or a cruciferous crop (cabbage, etc.). Look for varieties that have the resistance listed.
Q: With the harvest of garden produce upon us, here is a hint I learned years ago about peeling cucumbers. You may think some cucumbers are more bitter than others. The bitterness is not actually in the cucumber but in the way it is peeled. To prevent it from tasting bitter, peel it from the blossom end toward the stem end. See if you have any more bitter cucumbers. (Fargo, N.D., e-mail)
A: Sounds interesting! I haven't met a cucumber that I didn't like--yet. I never peel my own, eating them more or less like a carrot. I prefer the English Telegraph, a nice long, slender one, about 10 to 12 inches long. It is seedless and has a nice tender taste.
Q: I planted garlic and am wondering what to do with the seeds on the top. (Parkston, S.D.)
A: Garlic "seeds" can be sown this October, harvested as bulbs in July 2000, and the largest cloves sown that fall, and a harvestable crop taken in July 2001. You could also save some of your largest cloves from this year and sow in October for harvest next July.
Q: What is the proper method for deadheading daisy blossoms that have bloomed and died? (New Rockford, N.D., e-mail)
A: In deadheading any perennial that still has green tissue, simply remove the spent flowers back to the first set of leaves. You can do this by using a pocket knife and a piece of rubber hose around your thumb, or with some pinking shears.
Q: Can you tell me what is wrong with my cucumber and tomato plants? (Pettibone, N.D.)
A: Your plants appear to have the advanced stage of anthracnose and a bacterial leaf spot. First, I would suggest selecting only those plant cultivars that have disease resistance bred into them. Next, continue to rotate your plantings, tomatoes with beans, cucumbers with cabbage, etc. Avoid any overhead watering to keep this from recurring, and spray with a copper-based material to control further spread of the bacterial disease (if it hasn't developed too much). For the anthracnose, try Bravo or mancozeb as a protectant.
Q: Two different weeds seem to be taking over my lawn. The one with yellow flowers seems to be spreading fast and killing the grass. If you could tell me what it is and how to kill or control it, I would be grateful. (Minot, N.D.)
A: The yellow flowered weed is likely either black medic or oxalis. Not a problem either way, as several herbicides on the market will provide control. Weedone DPC amine or Trimec will do the job nicely for you.
The other one is probably field bindweed. It will take repeat applications of Trimec or Weedone to get rid of this one if it is well established.
Q: Some kind of grass or weed is in my lawn--here and there, not all over. What chemical will kill it and not the lawn? (Napoleon, N.D.)
A: The weed is foxtail, and it can be controlled with a pre-emergence herbicide containing pendimethalin next spring.
Q: Could you tell me what is happening to my hibiscus plant? It still has blossoms, but the leaves are turning yellow. Also, do you know anything about the Gerbera daisy? (Valley City, N.D.)
A: The hibiscus could be short on nutrients, or it is attempting to go into a rest period--known as dormancy.
The Gerbera daisy is an easily grown pot plant with daisy-like flowers. They come in a wide range of colors and need to be kept constantly moist and occasionally misted. They can be started from seed. The cultivar Parade will produce uniform, compact flowers--a very satisfying plant to grow if you have a bright spot that gets direct sun part of the day.
Q: How can I get rid of chickweed in my perennial bed? (Clearfield, S.D.)
A: Trimec will take care of the plant but not the seeds. There are several pre-emergence herbicides on the market that you can use next spring about the time the forsythia are in bloom. With properly timed application, you will eliminate most of this pest.
Q: Can you tell me why the leaves on my tomato plants are brittle, curl and have light-colored blotches? The problem seems to be spreading upward. I hope I can save my plant before it damages all of the green tomatoes on it. (Washburn, N.D.)
A: It appears your tomatoes are suffering from tomato mosaic virus--akin to tobacco mosaic virus--spread by handling (especially by smokers), leaf hoppers, etc. Unfortunately, there is not much one can do. If it is affecting only a couple of plants, then I'd suggest their immediate removal. If it is hitting many, then I suggest letting any green, mature tomatoes to ripen off the vine.
Q: We would like to move our perennial bed and are wondering when is the best time to do this. (Sisseton, S.D.)
A: An ancient rule of thumb applies fairly well to moving perennials: spring and early summer flowering perennials are moved in the fall after killing frosts; late summer and all bloomers get moved in the early spring when the soil thaws. As with many rules similar to this, I've broken them and gotten away with it, but I don't suggest you try it.
Q: A weed that is taking over my yard blooms in the spring and has tiny blue flowers. Can you tell me how to kill it? (Angus, Minn.)
A: Your weed is ground ivy--Glechoma hederacea--a tough one to control. Only repeat applications of a herbicide like Trimec will control it.
Q: The leaves of my mountain ash started turning color, and upon closer examination we found holes at the base of the trunk in three of our trees. Is there anything we can do to save these trees? Near these affected trees, there are a large oak tree and an apple tree that don't seem to have any symptoms. (Pekin, N.D.)
A: The mountain ash samples you sent show several problems--scab on the foliage, borer damage on the stems and some root rot at the crown. I advise removing the trees. Attempts to save them at this point would be an exercise in futility.
The oak should be OK, but because the apple and mountain ash are in the same family, I would keep a wary eye on that tree and take immediate action should it start to deteriorate.
Q: We used certified seed for our potatoes, and we hadn't planted any potatoes for five years. They are scabby with only one or two to a vine. What is wrong? I placed marigolds around my garden because I was told that they would get rid of bugs, but the bugs ate them all up, only leaving the stems. (Jamestown, N.D.)
A: Wow -- you do need help!
The scab on your potatoes is soil borne, and once the potatoes have it, there is nothing you can do. The best defense against this is to get cultivars that are known to be resistant to the disease. Some examples are Goldrush, Katahdin, Kennebec, Red Norland, Red Pontiac, Russet Norkotah and Superior.
You probably had the "nice" marigolds--deodorized hybrids. Next time try the stinky old-fashioned kind, they usually work better.
Q: I have two huge weeping birch trees in my yard, and each year they give off pods of brown material. These seeds, or whatever, get into flower beds and everything in our yard. It seems they also stop growth of some plants or hurt the soil. Can anything be done to stop these pods from forming? These trees are about 30 years old. (Regent, N.D.)
A: These are catkins for the birch tree--or seed. The problems they cause (messiness mostly) are a small price to pay for the beauty of these magnificent trees! You are fortunate to have them around for so long. Sorry, but I know of nothing that will prevent them from forming these catkins.
Q: Any advice on how I can transplant the wild flowers that I see alongside the road? They look like miniature sunflowers with the dark center. Also, I have some Ponderosa pines in my yard that are about 2 to 3 years old. Their center trunk is not growing straight but instead becoming curvy. Any tips on how to prevent or fix this? They are about 5 feet tall now. (Carrington, N.D., e-mail)
A: The best way is to gather seed and sow it where you want them to come up next year. They typically do not transplant well at this point in their life cycle.
Not much you can do about the Ponderosa pine with a curved trunk. Look at it this way--yours will have a unique character and a more "natural" appearance. Some of the most beautiful Ponderosa pines I've ever seen were wind twisted in the Rocky Mountains of Colorado.
Q: When is the best time to plant tulip bulbs, and how deep should they be planted? I also would like to plant some iris. Would I plant them the same as tulips? (Donnelly, Minn., e-mail)
A: Generally, tulips are planted about 6 inches below the soil surface and planted en masse at a site rather than individually. Think in dozens rather than individuals.
Iris, on the other hand, are planted just below the soil surface--about 2 inches. With iris, you are likely better off planting them in the spring to allow the roots to get established in the new location. I'm afraid they could be winterkilled from heaving if planted in the fall.
Q: My tomato plants were looking great and then this stuff attached itself to them. I did spray it with bordeaux mixture, but it didn't help. I enjoy plants, but I don't have any other place to plant them, so will this affect my plants next year? (Viborg, S.D.)
A: Your tomatoes have bacterial spot. It is a problem controlling diseases when you cannot rotate your crops. Be sure to clean the planting area completely of any debris, purchase disease-resistant cultivars and avoid overhead watering.
###
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