Your calendar and a soil thermometer will help you know the
proper planting time for your garden vegetables.
Many of the vegetables we plant are from the tropics. They
don’t like cold soils and won’t grow well in them. To get the
best growth, then, plant all transplants and seeds within a
certain soil-temperature range.
| Spring
Patience: Minimum Soil Temperatures for Planting * |
|
| Tomatoes, cucumbers, snap beans | 60º F |
| Sweet corn, lima beans, mustard
greens |
65º F |
| Peppers, watermelons, squash, southern
peas |
70º F |
| Okra, cantaloupe, sweet potatoes | 75º F |
| * Take readings on three
straight mornings at 1 to 2 inches for seeds and 4 to 6 inches for transplants. |
|
Planting too early, before the soil has had time to warm
up, can lead to seed rot, slow germination, poor growth and
disease.
For example, cucumber seeds usually take less than a week
to germinate in a soil of 70 degrees Fahrenheit. They could take
two weeks in 60-degree soil. Tomato transplants need a soil
above
60 degrees to grow. And setting out pepper plants before the
soil
is 70 degrees could stunt their growth for the entire growing
season.
You can buy a soil thermometer at a local nursery or
hardware store. Or order one from a gardening catalog.
This table provides a good general guide for minimum soil
temperatures for seeds and transplants.
