The USDA Zone info is a great tool for gardeners to help us determine 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.

The first chance to plant trailing portulaca in Northfield can be determined by reviewing the USDA zone info.

Planting Calendar for Trailing Portulaca

Frost tolerance for trailing portulaca:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant trailing portulaca until after the last frost because they do not do well in cold weather.

The earliest that you can plant trailing portulaca in Northfield 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. You probably don't want to wait any later than that or else your trailing portulaca may not have a chance to really do well. If you are starting your trailing portulaca indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Northfield. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Northfield is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Northfield there is a last frost after May 15 be ready to protect your trailing portulaca in the event of one of those late frosts.

USDA Zone Info for Northfield

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Northfield

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