One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Alton you can estimate when it's possible to plant garlic by referring to the USDA zone info.

Planting Calendar for Garlic

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

Since garlic are very cold tolerant you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant garlic in Alton 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 garlic and expect a good harvest is probably September. If you wait any later than that and your garlic may not have a chance to fully mature. Starting your garlic indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Alton. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Alton is an average the actual date of last frost is different every year. Half of the time in Alton you get a frost after April 15 so just be sure to be ready to protect your garlic if you have one of those late frosts.

USDA Zone Info for Alton

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Alton

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