impatiens wilting and dying after transplanting

by Myrna
(Sudbury Canada)

I grow my own impatiens from seed--for 15 years. I start them in the house and then put them in four packs in my greenhouse. I've never had trouble with them. This year 2 of them wilted at the stem in the greenhouse. I threw out the infected plants and soil, isolated the flat and drenched the soil with Benomyl. The rest of the plants seemed fine after a while--nice and healthy looking, just as are all the rest of my plants. When I transplanted some in my flower bed. within 2 days some were laying on the ground wilted. It seems that the stems get weak and slightly spongy at the soil level. I drenched the soil with Bordo mix and so far no more have died though a couple don't look so healthy. This morning I drenched all the plants in the green house with Benolyl. Should I also use Bordo mix on the soil in my beds? The plants planted there last year were gorgeous. I hate to plant any more until I can solve this problem. Is there any other fungacide I should be using?

Doug says that it sounds as if you have a fungal infection (most often referred to as stem rot or damping off) Repeated plantings of one plant in one place will encourage this as will damp and airless conditions in propagation. I don't use nor recommend chemicals such as Benomyl but instead find that increased air circulation in the seedling trays and garlic water drenches (a few cloves of garlic crushed and simmered in a few inches of water) will do the trick nicely.

Garden - the bordeaux mix should help but crop rotation is a very good idea. This is going to be particularly true now that you have a a problem going on.

A last note - using a lot of compost or compost tea in the garden is going to help in two fronts. The first is that soil microorganisms will attack some of the fungal growth and secondly stronger growing plants resist damage better than weak or nitrogen rich stems/plants.

Good luck.