When can I plant Diascia in Belleville, IL

One of the first steps we take when we are figuring out our gardening schedule is find our USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

A way of determining when to plant diascia is to look at the USDA zone info for Belleville.

Planting Calendar for Diascia

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

Since diascia do well in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

A good time to plant diascia
Possibly ok, but a risky time to plant diascia
Probably not a good time to plant diascia

The earliest that you can plant diascia in Belleville 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. Any later than that and your diascia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your diascia indoors.

Last Frost Date

In Belleville the average date of last frost happens on April 15. We should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Belleville is just an average our actual date of last frost changes from year to year. Since half of the time in Belleville it frosts late in the year after April 15 be ready to cover your diascia in the event of one of those late frosts.

USDA Zone Info for Belleville

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Belleville

You may be interested in our other planting guides for Belleville.