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

By using the USDA zone info for Walden you should be able to figure out 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 when the weather gets warmer.

You can not plant portulaca until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant portulaca in Walden 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 couple of weeks earlier by starting your portulaca indoors.

Last Frost Date

In Walden the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Walden is an average the actual date of last frost changes from year to year. Since half of the time in Walden last frost occurs after April 15 be ready to protect your portulaca if you have a late frost.

USDA Zone Info for Walden

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Walden

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