March 28, 2002

Hortiscope

Ronald C. Smith, Horticulturist
NDSU Extension Service

Q: You have had several items concerning peace lilies lately, but I still am not sure what is causing the edges of the leaves to turn yellow, then brown. I have trimmed the brown edges off (does this hurt the plant?) I really want to know how to keep this lily alive. It is from my dad’s funeral last summer. I read somewhere that it should be immersed in water until it is totally soaked, then let it drain thoroughly twice a week. I tried this, but it still seems to get brown. What am I doing wrong? (LaMoure, N.D.)

A: The water you are using is likely high in salts, especially this time of year. I suggest using distilled water for a couple of waterings, then cut your normal water half and half with distilled to see if that improves things. What has turned brown will stay that way, but the new emerging growth should be free of that problem. Don't worry. These plants can look bad, but it’s really hard to kill them!

Q: Is there an effective preemergent herbicide for an over the top application in my iris fields (4 acres), as Surflan is not available ? (Bismarck, N.D.)

A: The following herbicides are listed as cleared for iris: Acclaim Extra, Barricade, Dimension, Fusilade II, Gallery, Pennant, Snapshot, Treflan, and Vantage. Be sure to read and follow label instructions carefully.

Q: I have a question about my spider plant. On one of the baby stems there are these little brown humps. I tried picking one off and it just crumbled. It is just on one of the babies, and that baby has this waxy build up on it. What is this and what should I do about it? (E-mail reference)

A: It could be scale. I would discard that plantlet, and spray the rest of the plant with Neem oil or something similar that isn't toxic to humans or other warm-blooded animals.

Q: I have a spider plant with brown tips on the leaves, and brown spots in the middle. It is in a south window. I water it once a week with reverse osmosis water to make sure there isn't any salt in the water. I fertilize it every other week at half strength, and I like to give it a good misting every time I water. It isn't extremely unhealthy or anything, it has two long stalks with babies on it. I can't figure out what is wrong with it. Could it be getting too much light? It receives about three hours of bright sunlight a day. (Moorhead, Minn.)

A: As long as the plant is not receiving the brightest, most direct rays of the sun during the midday, that should not be a problem. My only remaining guess is that it may need repotting. Check to see where the soil level is in relation to the rim of the pot. If it is right up to the edge, then watering becomes difficult and the plant needs to be moved into a larger pot. From what you are telling me, it appears that you are doing everything right. We have had Chlorophytum plants in our house for over 15 years, and other than occasional tip burning they are literally a foolproof plant to grow for a houseplant.

Q: You had a request from a Moorhead resident about the Sheyenne tomato. Tanager Organic Seeds specializes in organically grown heirloom vegetable seeds. You can access the catalog at: www.angelfire.com/biz2/collectibles4u/seeds.html (Moorhead, Minn.)

A: Thanks! Your tip will make hundreds if not thousands of people happy. I checked the site out and it looks great.

Q: After about a bizillion years of wanting one, I finally received a shamrock plant for St. Patrick's Day. As the pot it is in is really very full, I think I should replant it soon. Can I keep it as a houseplant or does it have to be planted outside? If outside, should I plant it in the shade? Sun? Partial sun? Any advice you can give me will be greatly appreciated. (E-mail reference)

A: Wow! Think of all the history you have seen over all those years! You want to keep this as a houseplant, but you must understand that it goes through a rest or dormant period after blooming. I assume yours is in bloom right now, so I would allow it to complete this normal cycle, then as it declines, back off with the watering until the plant dies down completely. Then remove the tubers from the present pot and place in a 6-inch container and keep moist, not soaked. Be sure at least 1/2 inch of soil covers the tubers, and that there are no more than six tubers per container. As new growth begins, increase the watering and fertilize at least monthly with a dilute solution of houseplant fertilizer such as Schultz's or a similar product. Give the plant plenty of bright indirect light, along with some diffused morning sunlight if possible, and you should be able to enjoy it for another bizillion years or so!

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. Note to e-mail correspondents: please identify your location (city and state) for most accurate recommendations.

###

Source: Ron Smith, (701) 231-8161, ronsmith@ndsuext.nodak.edu
Editor: Gary Moran, (701) 231-7865, gmoran@ndsuext.nodak.edu