We had a rainy week here
in Ohio, and suddenly all of the gardeners started talking about Tomato
blight. Unfortunately, I've seen a lot of misinformation floating
around in that department. So this post is my attempt to debunk a
couple of myths.
Myth 1: Blight came in with my compost. While it's possible that you brought in Tomato Blight in one of your store-bought supplements, it's most likely this fungal disease floated through the air from someone else's garden to yours. Store-bought tomato plants can sometimes bring blight along with them. But unless the compost you bought was created from diseased tomato plants, it's unlikely a soil amendment is at fault.
2: I'll plant African marigolds and beat the blight that way. Tomato blight refers to one
of several different fungal diseases while African marigolds are used
to combat some species of nematodes. Tomatoes can (rarely) suffer from
nematodes, in which case you'll see enlarged knots on the roots,
yellowing leaves, and general slow growth. So, sure, plant a cover crop
of African marigolds in next year's tomato bed if you're certain you
suffer from nematodes. Otherwise, I instead recommend manual
blight-control techniques to deal with your ailing
I'm glad to report that our tomatoes enjoy Ohio much more than they did Virginia. I've pruned a couple of times to knock back septoria leaf spot, but our plants are still thriving despite the onset of the mildest of the trio of common tomato fungal diseases.