How to spot it

Lower leaves turn yellow, often on one side of the plant or one side of a leaf, then wilt. Cut the stem near the soil: the inside is streaked brown.

What it does

At first plants wilt in the heat and recover at night; then they die. The fungus lives in the soil for years.

What to do now

• Pull and throw away sick plants, roots and all.
• No spray cures it.

Keep it away next time

• Grow resistant varieties ("F" or "FF" on tomato tags).
• Move the crop to fresh soil or containers for several years.
• Clean tools and stakes after use.

Plants it affects

See also