One of the best tools that you have as gardeners to help us determine 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.

By using the USDA zone info for Polson it's possible to estimate when it's possible to plant portulaca.

Planting Calendar for Portulaca

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

Portulaca do not do well in cold weather which means that you have to wait until it warms up after the last frost before you can plant them.

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

The last month that you can plant portulaca and expect a good harvest is probably August. You probably don't want to wait any later than that or else your portulaca may not have a chance to fully mature. You can get started a little bit earlier by starting your portulaca indoors.

Last Frost Date

On average the last frost is on April 15 in Polson. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Polson is just an average the actual date of last frost will vary from year to year. Half of the time in Polson it frosts late in the year after April 15 so make sure that you are ready to cover your portulaca in the event of a surprise late frost.

USDA Zone Info for Polson

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Polson

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