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

The USDA zone info for Westminster can be looked at to determine 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.

Since portulaca require warm weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant portulaca in Westminster 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 grow to maturity. Starting your portulaca indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Westminster. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Westminster is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Westminster you get surprised by a frost after April 15 be ready to cover your portulaca if you have one of those late frosts.

USDA Zone Info for Westminster

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 Westminster

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