One of the best tools that you have as gardeners to help us estimate 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 portulaca in Ames can be figured out by referring to the USDA zone info.

Planting Calendar for Portulaca

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

Since portulaca are not cold tolerant you have to wait until after the last frost before you can plant them.

The earliest that you can plant portulaca in Ames 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. Any later than that and your portulaca may not have a chance to fully mature. If you are starting your portulaca indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Ames. It might get as low as -20°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Ames is not always accurate and the actual date of last frost changes from year to year. Half of the time in Ames there is a last frost after April 15 so just be sure to be ready to cover your portulaca if you have one of those late frosts.

USDA Zone Info for Ames

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Ames

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