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.

A way of making a decision about when to plant trailing portulaca is to look at the USDA zone info for Grand Forks.

Planting Calendar for Trailing Portulaca

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

It's probably not a good idea to plant trailing portulaca until after the last frost when the weather gets warmer because they are not cold tolerant.

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

The last month that you can plant trailing portulaca and expect a good harvest is probably August. If you wait any later than that and your trailing portulaca may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your trailing portulaca indoors.

Last Frost Date

On average the last frost is on May 15 in Grand Forks. You can expect an average low temperature of -30°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Grand Forks and it is different every year. Since half of the time in Grand Forks there is a last frost after May 15 be ready to cover your trailing portulaca if you have a late frost.

USDA Zone Info for Grand Forks

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Grand Forks

You may be interested in your other planting guides for Grand Forks.