One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant cleome in Zone 1a should be determined by checking out the USDA zone info.

Planting Calendar for Cleome

Frost tolerance for cleome:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant cleome until after the last frost because they do not do well in cold weather.

The earliest that you can plant cleome in Zone 1a is June. However, you really should wait until July if you don't want to take any chances.

The last month that you can plant cleome and expect a good harvest is probably July. If you wait any later than that and your cleome may not have a chance to fully mature. Starting your cleome indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is June 15 in Zone 1a. You can expect an average low temperature of -60°F in the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Zone 1a and it changes from year to year. Half of the time in Zone 1a it frosts late in the year after June 15 so always be ready to protect your cleome in the event of a late frost.

USDA Zone Info for Zone 1a

Here is the info for USDA Zone 1a.

Average Date of Last Frost (spring)	June 15
Average Date of First Frost (fall)	July 15
Lowest Expected Low	-60°F
Highest Expected Low	-55°F

This means that on a really cold year, the coldest it will get is -60°F. On most years you should be prepared to experience lows near -55°F.

Plants to Grow in Zone 1a

You may be interested in your other planting guides for Zone 1a.