The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's the best time to plant spearmint in Rock Island by reviewing the USDA zone info.

Planting Calendar for Spearmint

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

Since spearmint are very cold tolerant you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant spearmint in Rock Island 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. If you wait any later than that and your spearmint may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your spearmint indoors.

Last Frost Date

In Rock Island the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Rock Island and it can change quite a bit from year to year. Half of the time in Rock Island you get a frost after April 15 so just be sure to be ready to protect your spearmint in the event of one of those late frosts.

USDA Zone Info for Rock Island

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 Rock Island

You may be interested in your other planting guides for Rock Island.