Just reading through my Garden Gate magazine that came today. They have a paragraph entitled "Coleus Concerns". Basically they are saying that we need to take a good look at any coleus we buy next year. They have confirmed the presence of downy mildew on greenhouse coleus. This particular species of the mildew is only affecting basil and coleus. It spreads fast and can wipe out everything. Good air circulation is a must to prevent this. This is spread by infected soil, rain and insects.
Great magazine, everyone should get it!
Juanita
Article "Coleus Concerns"
Folks,
Juanita is right. There is a new downy mildew that attacks coleus. It came in from Europe a couple years ago and has spread throughout the greeenhouse industry. I've even seen it on material at major grower trade shows displayed by the biggest companies.
It is a species of Peronospora that is specific to Coleus and Basil. The symptoms are brown or black spots, fuzziness on the underside of leaves, leaf curling and leaf drop. It tends to prefer yellow or green types but can occur on other colors. Some varieties appear to be more resistant than others. It won't kill the plant but it will make it it pretty darn ugly. Many growers aren't even aware of the disease because it's so new, but there is a lot of educational material coming from the universities, so that is changing.
The good news is that it can be controlled with sanitation, good air movement around plants, low humidity, and fungicides. Copper-based fungicdes like Mancozeb are a good protectant. Systemic funcicides are needed for eradication. Keep your inside growing and propagating areas clean with chlorox or peroxide.
It's not the end of civilization as we know it. Just keep your eye out for unhealthy looking plants. Watch what you buy, what you swap, and Sidney et al., what you snip.
Chris
Garden Gate Magazine - HEAR! HEAR! YEAH. I recommend it, too. Wish it came every month!
Oh shoot! Another thing to watch for and worry over! The only thing I could hope would be for it to kill the stupid mealy bugs if I get the fungus! LOL
Thanks for the great info Chris and Juanita. I'll bookmark this thread and will certainly pay close attention next year.
Chris,
Strange you should mention coleus and basil in the same breath. The flower is almost the same and the growth habits are close. Are they related?
Sidney, are you paying attention?
Innocent Hap
Great info I will watch what I get. Oh..Garden Gate magazine is published here in Des Moines, along with a plethora of other garden and living magazines.
Hap,
Yep. Coleus is in the mint family along with basil, lamium, monarda, salvia, rosemary, lavender, oregano, perilla, thyme, plectranthus, and mint, among others.
Chris
Thanks, Chris.
You know last week I went through and wiped out every Red YES in the Coleus Forum.
I really appreciate the warning and carry a magnifying glass in my pocket to inspect before I snip.
;)
Sugar, you have to be a sight to behold. PMP
Thanks for the magazine tip...just sent link to MIL as my Christmas wish item::)) I think I just want magazines now:) I love the handyman too.
Found this helpful. How long can spores live? Can last years area infest this years area, etc?
I think we need a sticky or thread devoted to what is n
known and what has been tried that works. I don't know how to do this...Help anyone?
Judy