Disease
Early blight
What it is
A fungal disease of tomatoes and potatoes showing brown spots with concentric rings ("target spots") on older leaves, working upward.
How to identify it
Dark brown spots with target-like rings and a yellow halo, starting on lower leaves. Leaves yellow and drop.
How to treat it
Remove affected lower leaves and improve airflow. Copper-based sprays can slow spread if applied early.
How to prevent it
Mulch to stop soil splash, water at the base, rotate solanums yearly, and space plants well.
Plants affected
Treatment guidance is general and organic-first; check current advice for your area before using any product.