Working with resistance cultivars: Not all tomato and potato varieties have the same early blight resistance.
Sanitation: Make an effort to clean and maintain your fields’ close surroundings from weeds as often as possible.
The sooner the better: It’s easier and more cost effective to overcome early blight and control it during the initial stage of infestation. Make it a routine to monitor the field regularly and search plants for the presence of the above symptoms on a weekly basis.
As with any moisture-favoring disease, various agro technical measures can be taken during crop growth to reduce the chances of an infection and spread:
Improve air circulation: In closed structures, promote the drying of foliage and shorten the duration of wetting periods by introducing net curtain vented areas.
Proper soil drainage: The presence of standing water will promote the spread of late blight.
Cover the ground with polyethylene sheets to reduce water evaporation from the soil.