CROP | Min °C. | Optimum Range°C | Optimum °C | Max °C |
Asparagus | 10 | 15-30 | 24 | 35 |
Bean | 15 | 15-30 | 27 | 35 |
Bean, Lima | 15 | 18-30 | 30 | 30 |
Beet | 5 | 10-30 | 30 | 35 |
Cabbage | 5 | 7-35 | 30 | 38 |
Carrot | 5 | 7-30 | 27 | 35 |
Cauliflower | 5 | 7-30 | 27 | 38 |
Celery | 5 | 15-21 | 21* | 30* |
Chard, Swiss | 5 | 10-30 | 30 | 35 |
Corn | 10 | 15-35 | 35 | 40 |
Cucumber | 15 | 15-35 | 35 | 40 |
Eggplant | 15 | 24-32 | 30 | 35 |
Lettuce | 2 | 5-27 | 24 | 30 |
Muskmelon | 15 | 24-35 | 32 | 38 |
Okra | 15 | 21-35 | 35 | 40 |
Onion | 2 | 10-35 | 24 | 35 |
Parsley | 5 | 10-30 | 24 | 32 |
Parsnip | 2 | 10-21 | 18 | 30 |
Pea | 5 | 5-24 | 24 | 30 |
Pepper | 15 | 18-35 | 30 | 35 |
Pumpkin | 15 | 21-32 | 35 | 38 |
Radish | 5 | 7-32 | 30 | 35 |
Spinach | 2 | 7-24 | 21 | 30 |
Squash | 15 | 21-35 | 35 | 38 |
Tomato | 10 | 15-30 | 30 | 35 |
Turnip | 5 | 15-40 | 30 | 40 |
Watermelon | 15 | 21-35 | 35 | 40 |
*Daily fluctuation to 10 degrees or lower at night is essential.
From James Edward Knott, Handbook for Vegetable Growers, John Wiley& Sons, Inc., New York, 1357, p. 8. Secondary source: “How to Grow More Vegetables than you ever thought possible on less land than you can imagine”. John Jeavons, Ten Speed Press, California.