One of the best tools that you have as gardeners to help us figure out 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 reviewing the USDA zone info for Alton you will be able to determine when it's a good idea to plant coral bells.

Planting Calendar for Coral Bells

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

You can plant coral bells a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant coral bells 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 coral bells and expect a good harvest is probably September. If you wait any later than that and your coral bells may not have a chance to really do well. You can get started a few weeks earlier by starting your coral bells indoors.

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.

Keep in mind that USDA zone info for Alton is not always accurate and the actual date of last frost is different every year. Half of the time in Alton last frost occurs after April 15 so be sure to be ready to protect your coral bells in the event of a surprise late frost.

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.