One of the first steps you take when you are getting a good idea 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.

You can figure out when it's possible to plant black eyed susans in Alton by reviewing the USDA zone info.

Planting Calendar for Black Eyed Susans

Frost tolerance for black eyed susans:	Not tolerant of frost.
When to plant:	After the last frost.

Since black eyed susans are not cold tolerant it is important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant black eyed susans in Alton is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant black eyed susans and expect a good harvest is probably August. Any later than that and your black eyed susans may not have a chance to really do well. If you are starting your black eyed susans indoors then you might be able to get away with starting them a few weeks 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.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Alton and it changes from year to year. Since half of the time in Alton last frost occurs after April 15 be ready to cover your black eyed susans 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.