Hi, folks,
I'm reposting this from the perennial forum, where I got some sympathy, but no diagnosis. Every year or so some of my grandiflorum or belladona delphinium produce very sparse florettes, and the grandiflorum produce distorted leaves. I only have a picture of a grandiflorum - not sure what happens with leaves of belladonna, as they didn't have a problem this year. Any idea what's going on?
TIA
LAS
Sorry nobody's answered you yet--I don't see any signs of insects, fungus, etc so I'd have to guess something cultural. I don't grow them but from what I've heard they can be a little temperamental, so it could be if something's just a little off in water, sun, nutrient levels, etc that could make it behave differently.
Is there a possibility of herbicide damage? Even if the chemical is used at a distance, the volatile oils can spread through the air and cause distortion on plants that it touches.
My DH put some roundup in a little plastic cup, and when he was done applying it by paintbrush on some weeds in tight spots, he left it sitting on the arm of a bench. Next to the bench is a Clerodendron (bleeding heart vine). About a week later, I noticed the tell tale signs of herbicide damage in the curling and distorted leaves. And only on that side of the plant.
Herbicides can cause all kinds of weird things to happen to plants, and at very low levels.
Do you have a picture of the distorted leaves? Something I've had trouble with, that not even the extension people seemed familiar with, was 'Broad Mites'. They actually poison the plant with some kind of chemical that curls and distorts the new growth--very ugly. They are very difficult to see, even with a microscope, but I think I'd recognize the damage. Or, you can do a google image search for 'Broad Mite Damage'. Something to consider anyhow . . .
Broad Mites rings a bell. Maybe someone else suggested it too. Were you able to come up with something to deal with them?
TIA
LAS
Long story short-no, not a total eradication. I have to be diligent now because they are in my yard. They may still be in my house. I use impatiens as indicator plants. It was a beautiful doggone impatiens they came in on. I'd never heard of them before. But I did learn a bit. The males carry the females to the newest growth. Most bugs have a tendency to move upwards. These mites seem to do the same thing. Wherever I found distorted growth, I would cut that section off and just be vigilant about checking and pruning. Some things I threw away. I'll be more diligent next year about not planting things they like, because I don't want to increase their numbers in my yard by giving them a host plant. Here are things I found they really liked:
peppers, impatiens, black-eyed Susan vine, dahlias, eggplant, zinnias, celosia, lemon balm, larkspur, tomatillos.
Other things I've heard are hosts (but I didn't see damage on) were: tomatoes, mums, snapdragons & parsley.
I'm sure there's more in both lists, but that just pertains to what I was growing. I try to garden organically, and didn't have much luck with sprays-impatiens are so darn sensitive that even soap spray killed them.
I'm using neem for thrips & fungus gnats, but it might be a good preventive. You could read up on that or see if anyone else knows.
so, my method: vigilance, indicator plants mixed in, prune out damage, rinse plants every few days, throw out plants that I can't get cleaned up.
