One of the first steps you take when you are determining 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.

You can estimate when you can plant brussels sprouts in Zone 4a by using the USDA zone info.

Planting Calendar for Brussels Sprouts

Frost tolerance for brussels sprouts:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Brussels Sprouts tend to make it in moderate cold which tells us that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant brussels sprouts 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 brussels sprouts and expect a good harvest is probably August. Any later than that and your brussels sprouts may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your brussels sprouts indoors.

Last Frost Date

In Zone 4a the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Always keep in mind that USDA zone info for Zone 4a may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Zone 4a you get a frost after May 15 so just be sure to be ready to protect your brussels sprouts in the event of a 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.