One of the first steps you take when you are making a decision about your gardening schedule is find your 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 Zone 4a can be reffered to in order to determine when you can plant evolvulus.

Planting Calendar for Evolvulus

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

It's probably a bad idea to plant evolvulus until after the last frost has passed because they require warm weather.

The earliest that you can plant evolvulus in Zone 4a 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 evolvulus and expect a good harvest is probably August. Any later than that and your evolvulus may not have a chance to really do well. Starting your evolvulus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4a. In the coldest months of winter you can expect an average low temperature of -30°F.

Since the USDA zone info for Zone 4a may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Zone 4a last frost occurs after May 15 so make sure that you are prepared to protect your evolvulus if you have a surprise late frost.

USDA Zone Info for Zone 4a

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 Zone 4a

You may be interested in your other planting guides for Zone 4a.