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 first opportunity to plant snow-in summer in Zone 4a should be determined by referring to the USDA zone info.

Planting Calendar for Snow-in Summer

Frost tolerance for snow-in summer:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Snow-in Summer tend to make it in some cold which means that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant snow-in summer in Zone 4a is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant snow-in summer and expect a good harvest is probably August. You probably don't want to wait any later than that or else your snow-in summer may not have a chance to really do well. You can get started a few weeks earlier by starting your snow-in summer indoors.

Last Frost Date

In Zone 4a the average date of last frost happens on May 15. You should expect an average low temperature of -30°F in the coldest months of winter.

Keep in mind that USDA zone info for Zone 4a is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 4a you get surprised by a frost after May 15 so be sure to be ready to cover your snow-in summer in the event of one of those late frosts.

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.