Varieties labeled as “heat tolerant” will perform relatively well (compared to other varieties within their crop group) when exposed to hot weather. The Johnny’s Research Team assigns the Heat Tolerant symbol to individual varieties within crop groups that traditionally do not perform well in the heat (as opposed to warm season crops that thrive in the heat); we do this to guide growers to more suitable options. In addition to trialing heat-tolerant versions of cool-weather crops such as broccoli, cauliflower, and lettuce, we also seek out highly heat-tolerant versions of warm weather crops; for example, tomatoes that demonstrate the ability to set fruit even under heat stress. See individual product copy descriptions for variety-specific information.
148 Products
Sort By:
Breen
Organic Pelleted Lettuce Seed
Early producer of truly compact mini heads with bronze-red color.
Red Cross
Organic Pelleted Lettuce Seed
Large and fancy, heat tolerant red butterhead for stunning display.
Starfighter
Pelleted Lettuce Seed
Uniform, disease-resistant green leaf with excellent heat tolerance.
Happy Rich
(F1) Broccoli Seed
Vigorous mini broccoli for successful summer crops and sweeter flavor.