NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665
March 30, 2000
Ron Smith, Extension Horticulturist
North Dakota State University
Q: My praying hands plant has brown spots on the edge of its leaves. What could it be from? I don't water my plants unless they feel dry when I feel the top of the soil. The Christmas cactus is doing really good and blossoming along with the rest of my plants. (Carrington, N.D.)
A: The prayer plant (Maranta spp.) is sensitive to being underwatered. While such treatment is good for Christmas cacti, it causes problems with this species. Unlike many (if not most) houseplants, the soil should be kept moist at all times--do not allow it to dry out.
Other possible causes of brown leaf spots could be dry air or too much direct light. Mist the foliage often with distilled water, and keep in mind that the sunlight intensity and duration is on the increase now, so exposure that wouldn't cause harm two or three months ago could be the culprit now. Be sure to remove any badly affected leaves.
Q: I have a space in my yard, about 150 square feet, which I plan to make into a perennial flower garden. My concern is that I do not have enough room in my home to start the seeds early. Could you please give me some advice as to when and how to plant? I would like to get started early enough so I can enjoy the blossoms for a while. (Langford, S.D.)
A: Important to keep in mind is the fact that some seeds need light to germinate, while others don't. That little detail is often the difference between success and failure. The source for that information is usually on the seed packet or in the catalog where you made your purchase.
Q: I found your answer about the pear slugs to be very helpful, but my problem is that I seem to have them inside my house. I don't know where they came from. I think that I only have one indoor houseplant. Do you think they are in it? Or is it possible that they are in the house for no apparent reason?
A: If they are truly pear slugs, I assure they are not in the house for no apparent reason. If they are, they will soon be dead! The female lays her eggs on a food source unless some pheromone or other type scent got her off course. They die with just a spray of insecticidal soap.
Q: I was reading one of your columns and you said to replant a peace lily in a high-humus planting soil. I have one that needs to be replanted, but when I went to get some planting soil I could not find one that said it had a high percentage of humus soil. What do I look for on the label?
When I repot the peace lily do I need a deep pot, or will a more shallow one be better? Also, do the brown trunk-like things that the leaves come out of need to be put deeper, or should I leave them sticking out as high as they are? (Forman, N.D., e-mail)
A: I know it is tough to sometimes find the high-organic potting soil. If you cannot find one labeled so, then use African violet potting soil, which has sufficient organic matter in it. You could also purchase what is on the local market and cut it with about 50 percent by volume with peat moss.
I would get a large, deep pot to provide more stability. Peace lilies can get fairly large. Plant them up to that point on the corm where the leaves originate. Keep the media moist but not saturated, and provide the plant with bright, diffused light for flowering. Do not set in full sunlight. Fertilize about every two months.
Q: I am going to buy some shop lights to start my cucumbers inside and was wondering if it would be better to buy 8-foot bulbs that are 60 watt or 4-foot bulbs that are 40 watt. Does it matter? There is also one called "high output" that is 110 watt.
I was reading in the book "Great Garden Shortcuts" that a good way to start cucumbers is in little plastic pint baskets that strawberries come in. You line it with paper towels or newspaper and then snip off the bottom of the box when planting. I've heard that cucumbers are very touchy when you disturb their roots, and I thought this might be a good idea. What do you think? Would you leave about three plants per box? How many per hill? (e-mail)
A: The shop lights selection would make little difference. You would simply have to have the lower watts closer to the seedlings and run them for a longer time. Generally, the 4-foot bulbs work best, with one being a "cool white" and the other being a "warm white" type. For what you are going to use them for, I would suggest staying with the 40 watt.
Sounds like a good idea with the strawberry baskets. Leaving three per basket and hill would be appropriate. They are fussy about being moved once they have started, so either direct sow or transplant as you have described. Might not hurt to do both to spread the season out a little.
Q: We have a large (40-foot) white pine in our backyard in south Fargo. All winter it has been dropping the last inch to 1.5 inches of the ends of its branches. The ground is covered with these short pieces of pine branches. They are not yellow and do not look diseased. My sister who has a cabin in northern Wisconsin has reported that they were there this past weekend and the same thing is evident with the pines around their cabin. She indicated that there the little pieces even have pine cones attached. Any thoughts as to what is happening? (Fargo, N.D., e-mail)
A: If you look closely at the branches that have dropped, you will note that it is a clean break. The critter responsible for this is a fur-tailed, cute little bounder known as a squirrel. I have the same thing being done to my ponderosa pines as well. For some reason they get into the tree and like to nip the ends off--6 inches to 12 inches at a time in some cases. While I don't like their "random pruning," there is little I can do about it unless I want to try trapping. My trees have long since lost their nice symmetrical shape, but other than that, they are doing OK.
Basically, I'd say you have nothing to worry about. You might consider putting some corn and sunflower seed out to give them something else to chew on!
Q: I have a customer who is having problems with small, white nematodes in his tomato fruits. He is quite sure this is a nematode as they are just big enough to see and worm-like in appearance. Also, this guy is a retired entomologist, who did most of his work in the area of beetles, but is quite sure this is a nematode.
Have you heard of this being a problem anywhere else? How can he control this pest and keep his garden produce safe to eat? This is a relatively new garden site and would be difficult to move to another location. (Bottineau, N.D., e-mail)
A: With all due respect to the retired entomologist, I really do not believe they are nematodes for two reasons. First, I have never seen one that is visible to the naked eye. And second, they are generally not fruit attackers but prefer instead to work on the root system.
If he insists that they are nematodes, I am not going to argue with him, only suggest that he interplant his tomatoes with plants that serve as a nematicide. The best one, based on research and its ready availability, is the African marigold, which produces oxygen radicals that block steps in nematode metabolism.
My bet is that he is seeing the larvae of the click beetle--young wireworms. It is unusual for them to be after tomatoes, but they are common pests on potatoes, which are in the same family.
Tell your client to clean the garden well of any debris this spring, turn the soil over early and stake the tomatoes to keep the fruit from contacting the soil. All of this should help, no matter what it is that is going after his tomatoes!
Q: I am trying to establish a garden fruit and nut orchard. Some of the apple trees that I planted last year are straight as a rod, and some are quite crooked. All are staked. In time will the crooked whips straighten out? (Burlington, Vt., e-mail)
A: Here is what I would suggest:
Remove the stakes. I'm betting you have more material in the stakes than you do wood in the trees. I promise you they will not blow over at this stage in their lives. Natural movement is better for them, as it will help to build caliper (trunk thickness and strength) faster. Staking, which inhibits natural movement, slows down this process.
Do not prune anything for now, and probably not for the next two or three years. Those trees will need every square inch of leaf surface area possible to get established. After that, prune lightly about this time of year--late March or early April.
Don't worry about whether they are straight or crooked right now. Nature will take care of that in time. Consider how we humans come into the world, and look at how we develop! Simply give them a chance to get established and adapt to where they are.
Q: This is in response to the inquirer who asked about the saguaro cacti. Here is some information I recently discovered while in Arizona. A saguaro growing from a seed will grow only 4 inches in the first 10 years. It takes 50 years for a cactus to reach 10 feet. After 18 feet--and 60 years--it will begin to grow an arm. So the reader will not see much change from year to year in the saguaro cactus. (Fargo, N.D., e-mail)
A: Now that I have read what you said, part of that information comes back from when I was living in Arizona some 15 years ago. Thanks for the refresher!
Q: Many of the potatoes from our garden were greenish under the skin last year, and I was concerned that they were not good to eat. I would like to know the cause of this greenishness. (Bowdon, N.D., e-mail)
A: The cause of potatoes turning green is light interacting with the epidermal tissue, which causes chlorophyll to form. Irish potatoes are really underground stems, and when exposed to light for any length of time, the spuds will turn green. That green color causes a bitterness in the potatoes, and possible stomach upset, and too much green potato consumption can cause poisoning. They will lose their green if they are returned to total darkness for five to seven days and will be OK to eat afterward. If when peeling the potatoes for cooking some green should show up, simply peel it away to the white and everything will be OK.
Q: I have a double red hibiscus that has gotten very leggy. It is in a 10-inch pot in the south window. I know I should cut it back, but it won't quit blooming. And the leaves are turning yellow on the bottom half of the plant. Can I cut it back even if it has buds on all of the stems? What can I feed it to stop the yellowing? (e-mail)
A: The hibiscus needs a rest! Let it go dormant and then cut it back hard to start over again. They will typically get leggy in a household environment. Once the leaves have dropped off, cut it back and set it outside for the summer. Water it when the rain is insufficient, fertilize once a month with a complete fertilizer and you will be rewarded with some more beautiful blooms.
Q: I have a question on asparagus. I have a lot of weeds in my patch. If I put leaves over the patch and leave it there, can they come up? If not, what can I do? (e-mail)
A: Yes, the asparagus will come up through the leaves, but depending on the weeds you have growing amongst them, so may some of the weeds. I suggest following through with your plan to use the leaves, and then carefully "wick-wipe" any weeds that come through with Roundup to kill them. Sooner or later, though, you will have to face the fact that the asparagus bed will need to be re-set in a weed-free area, as the weeds compete for water, nutrients and space.
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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