Tomato plants

[Bambito]

Our tomato plants were doing great. Now all of a sudden they have spots all over them and have stopped producing. Any ideas of what we should do?

[delcecchi]

"early blight"

Quote:

Symptoms of early blight usually appear near the end of the season, though symptoms may appear earlier. Brown lesions first appear on older, lower leaves, and spread up toward new growth. Lesions are small (1-2 mm), dry, and papery and may develop characteristic dark concentric rings of raised and necrotic tissue. Leaf tissue often turns chlorotic (yellow) at the edge of the lesion. As the disease progresses, the entire leaf can become chlorotic and then necrotic (brown). Severely infected tomato plants may become completely defoliated exposing fruit to sunscald. Infected potato leaves, however, usually do not fall off.

Lesions may also develop on the stems. These lesions begin as small, dark, slightly sunken areas that enlarge and may develop the target-appearance as on the leaves.

Quote:

Several foliar fungicides are registered for early blight. Mancozeb, chlorothalonil and copper are effective against early blight when applied at approximately 7-10 days intervals. Spraying should commence at the first sign of disease or immediately after bloom.

Plant varieties that are resistant or have a lower susceptibility to early blight.

[laker1]

Mine get the blight quite often and it starts showing up about the time you have small green tomatoes.

[Tom Sawyer]

Once it is in your soil, it's usally there for good. Remember to rotate crops from year to year and mulch under your plants, even if it's just newspapers. Diseased plants should be thown in the trash after the growing season, to prevent spread. I always remove any bad bottom leaves at the first sign of troble, and then add more mulch around plants. This usally buys enough time to get a decent harvest.

Mulching can really help to keep the soil born disease off your plants.