All the root, leaf, and flower bud vegetables like cool weather. With the exception of peas and fava beans (which like cool weather), all the fruiting vegetables like warm weather.

It is interesting that vegetable seeds are programmed with response to soil temperature. For example, lettuce, spinach and turnip will germinate at soil temperatures as low as 45 degrees. Peas and most other root and leaf vegetables need about 50 degrees. Sweet corn will germinate at about 55 degrees. Beans need about 60 degrees. Cucumbers, melons, squash, tomatoes and peppers need about 65 degrees soil temperature to sprout.

Hardy (cool) vegetables will withstand temperatures down to the mid twenties without damage. They thrive with day temperatures in the 50’s and 60’s. Tender (warm) vegetables can be damaged by a 32 degree frost. Warm vegetables make very little growth until temperatures reach the 70’s.

Potato is in a class by itself. Potatoes grow well in cool weather and tubers will sprout when soil temperature is in the 50’s. However potato plants will freeze at 32 degrees. Since it takes about 3 weeks for a potato to come up, it is safe to plant now. We don’t have enough warm weather for sweet potatoes to do well here.

Hardy (Cool) Vegetables

Pea, Fava Bean, Radish, Turnip, Rutabaga, Beet, Onion, Garlic (plant in the fall), Carrot, Parsnip, Horseradish, Lettuce, Endive, Spinach, Mustard, Collards, Kale, Swiss Chard, Kohlrabi, Cabbage, Broccoli, Cauliflower, Brussels Sprouts, Pac Choi, Celery, Asparagus, Rhubarb, Most Culinary Herbs except Basil

Tender (Warm) Vegetables

Tomato, Pepper, Egg Plant, Cucumber, Squash, Pumpkin, Melon, Bean, Okra, Sweet Corn, Basil