Your Impatiens Might Have Downy Mildew If ...
Use this checklist as a starting point to scout for the disease rather than scramble for solutions to it.
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Downy mildew on impatiens -
Notice how the underside of the leaf on the right has a light fuzz present. -
Check out the impact downy mildew had on these impatiens.
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Growers across the country are scrambling for solutions, with the discovery of downy mildew on impatiens in the U.S. landscape. Look for these symptoms in the greenhouse when you’re scouting your impatiens crop this year:
• Plant foliage that’s yellowish or pale green in color
• Leaves that curl downward
• Leaves that are distorted
• Undersides of leaves that have white or light gray fuzz present
• New and emerging leaves that are small and a discolored yellow or pale green
• Flower buds that fail to form
• Stunted plant growth
If you see one or more of these symptoms on a plant, immediately seal it in a plastic bag before removing it from the greenhouse. Get it to a diagnostic lab for further testing.
Additionally, when spraying for downy mildew, there are three important things to remember when applying fungicides:
1. Apply fungicides preventatively.
2. Rotate among products with different modes of action to prevent resistance.
3. Be timely in re-applications.
Laura Drotleff is a freelance writer based in Willowick, Ohio. She spent seven-plus years as an editor on Greenhouse Grower. Reach Drotleff at ldrotleff@gmail.com.
Comments (2)
Janelle (Sun Apr 22 17:23:48 2012)
I actually have a question about downy mildew not a comment. We have a small garden center in Ohio and have already thrown away or first round of impatien plugs we received from a broker in Michigan. They appeared to have downy mildew. We purchased a second round of plugs from another supplier and they seem to be fine until today 4/22. I watered a number of flat and other things but noticed a fine cloud or poof of smoke when I attempted to water the new impatiens. Nothing else in the greenhouse reacted like that to the watering that we do daily. Is that another sign of mildew and will it infect our other plants? What would you recommend using on the impatiens or possibly the entire greenhouse including veggies?
kay porter (Wed Feb 8 21:31:31 2012)
what is a good funguiside to use i also have this comsume my petunia posey bags how can i stop this?
