One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of making a decision about when it's possible to plant cleome is to examine the USDA zone info for Zone 4a.

Planting Calendar for Cleome

Frost tolerance for cleome:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since cleome require warm weather it is important to wait until after the last frost before you can plant them.

The earliest that you can plant cleome in Zone 4a 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 cleome and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cleome may not have a chance to really do well. You can get started a couple of weeks earlier by starting your cleome indoors.

Last Frost Date

The average date of last frost is May 15 in Zone 4a. In the coldest months of winter you can expect an average low temperature of -30°F.

Always keep in mind that USDA zone info for Zone 4a may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 4a it frosts late in the year after May 15 be ready to protect your cleome in the event of one of those late frosts.

USDA Zone Info for Zone 4a

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 Zone 4a

You may be interested in your other planting guides for Zone 4a.