The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to determine when to plant pentas by reviewing the USDA zone info for Williston.

Planting Calendar for Pentas

Frost tolerance for pentas:	Not tolerant of frost.
When to plant:	After the last frost.

Pentas are not cold tolerant which means that it is important to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant pentas in Williston is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant pentas and expect a good harvest is probably August. Any later than that and your pentas may not have a chance to grow to maturity. If you are starting your pentas indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Williston. In the coldest months of winter you should expect an average low temperature of -30°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Williston and it changes from year to year. Since half of the time in Williston you get a frost after May 15 be ready to cover your pentas if you have a surprise late frost.

USDA Zone Info for Williston

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Williston

You may be interested in your other planting guides for Williston.