Re: [tomato] Yellowing leaves -- does EVERYONE have early

Margaret Lauterbach (Tomato@GlobalGarden.com)
Wed, 26 Jul 2000 11:13:27 -0600

At 10:04 AM 7/26/00 -0700, you wrote:
> From reading all the traffic on this listserv, it
>sounds like almost everyone over the whole nation has
>some form of early blight on their tomatoes. According
>to a recent article in the Washington Post (see below)
>it has to do with spores being kicked up from the
>ground onto the leaves of the plants. My plants now
>are just long, tall stalks with green tomatoes here
>and there and with a tuft of green leaves at the very
>top!
>
>Does anyone know how to avoid this next year? I've
>tried the copper and the fungicide, and nothing seems
>to stop the progress of the disease.
>
> From the Washington Post Home Section, 7/20/2000
>
>Tomatoes:
>
>Last year, the drought squeezed the life out of
>America's favorite vegetable. This year, excessive
>rain is taking a different toll. Gardeners are finding
>the sheer biomass outgrowing the cages. Stems sprawl,
>strain, and collapse. Don't try to untangle the cage
>from the plant; the stems are easily damaged. One fix
>is to take three tall, wood stakes and drive them in
>against the out rim of the case. They should stick up
>above the wire, so the top of the tomato plant can be
>corralled within the stakes using twine.
>
>Another option is to give the plan a haircut. Top it,
>says Jon Traunfeld, of the Maryland Home and Garden
>Information Center. Even if you lose flowers and young
>fruit now, the plant will produce a bountiful harvest
>in its new compact state.
>
>The other more serious problem is leaf yellowing.
>Lower leaves naturally discolor as they age, but if
>the discoloration is accompanied by brown spots and
>lesions, you have a disease named early blight. A lot
>of gardeners are reporting these symptoms now.
>Uncontrolled it can wipe out a tomato plant.
>
>Traunfeld say tomato growers should remove and discard
>affected leaves and lay a thick mulch because fungal
>spores on bare soil are kicked up onto the leave by
>rainfall and gardener's hose.
>
>The disease can be controlled by sprays, including a
>fungicide called Daconil 2787, or organically using a
>liquid copper spray or fungicidal soap.
>
>Don't compost infected leaves.

Apply thick mulch BEFORE blight spores get started. We seldom get blight on 
tomatoes in my area (southwest Idaho) because our climate is dry. But we 
did have a couple of springs in which black spot hit roses and some 
reported blight (mainly late blight) on potatoes and tomatoes. There is a 
Green Light product that uses Neem and it is a fungicide (and other 
things), and should be fairly benign. Some who get attacked with early 
blight regularly grow tomatoes in plastic-covered tunnels to prevent 
blight. Mulch by itself should go a long way to preventing blight, 
however.  Margaret L