The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Yankton you can figure out when it's the best time to plant portulaca 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 has passed.

You can not plant portulaca until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant portulaca in Yankton 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. If you wait any later than that and your portulaca may not have a chance to really do well. If you are starting your portulaca indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Yankton. In the coldest months of winter you can expect an average low temperature of -20°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Yankton and it will vary from year to year. Since half of the time in Yankton last frost occurs after April 15 be ready to protect your portulaca in the event of one of those late frosts.

USDA Zone Info for Yankton

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 Yankton

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