One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

By checking out the USDA zone info for Willowbrook you should be able to determine when you can plant spearmint.

Planting Calendar for Spearmint

Frost tolerance for spearmint:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Spearmint are one of those plants that can tolerate quite a bit of cold weather which tells us that you can get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant spearmint in Willowbrook is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant spearmint and expect a good harvest is probably September. You probably don't want to wait any later than that or else your spearmint may not have a chance to grow to maturity. Starting your spearmint indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Willowbrook. In the coldest months of winter you can expect an average low temperature of -15°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Willowbrook and it is different every year. Since half of the time in Willowbrook there is a last frost after April 15 be ready to protect your spearmint if you have a late frost.

USDA Zone Info for Willowbrook

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Willowbrook

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