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 should be able to determine when you can plant diascia by looking at the USDA zone info for Edwardsville.

Planting Calendar for Diascia

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

Since diascia do well in moderate cold you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant diascia in Edwardsville 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 diascia and expect a good harvest is probably September. If you wait any later than that and your diascia may not have a chance to fully mature. If you are starting your diascia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Edwardsville. In the coldest months of winter you should expect an average low temperature of -10°F.

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 Edwardsville and it is different every year. Half of the time in Edwardsville last frost occurs after April 15 so always be ready to cover your diascia in the event of a surprise late frost.

USDA Zone Info for Edwardsville

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 Edwardsville

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