One of the best tools that you have as gardeners to help us estimate 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.

The first chance to plant calendula in Bethalto should be determined by checking out the USDA zone info.

Planting Calendar for Calendula

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

Calendula tend to make it in moderate cold which means that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant calendula in Bethalto 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 calendula and expect a good harvest is probably September. If you wait any later than that and your calendula may not have a chance to really do well. If you are starting your calendula indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Bethalto the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Keep in mind 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 Bethalto and it changes from year to year. Since half of the time in Bethalto it frosts late in the year after April 15 be ready to cover your calendula in the event of a surprise late frost.

USDA Zone Info for Bethalto

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 Bethalto

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