Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant impatiens in Collinsville should be determined by looking at the USDA zone info.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Impatiens require warm weather which means that it is important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant impatiens in Collinsville 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 impatiens and expect a good harvest is probably August. Any later than that and your impatiens may not have a chance to grow to maturity. Starting your impatiens indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Collinsville. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Collinsville is an average the actual date of last frost will vary from year to year. Since half of the time in Collinsville it frosts late in the year after April 15 be ready to cover your impatiens in the event of a late frost.

USDA Zone Info for Collinsville

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 Low	0°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 Collinsville

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