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.

By reviewing the USDA zone info for Collinsville you should be able to estimate when it's a good idea to plant scarlet pimpernels.

Planting Calendar for Scarlet Pimpernels

Frost tolerance for scarlet pimpernels:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Scarlet Pimpernels do ok in moderate cold which tells us that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant scarlet pimpernels in Collinsville is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant scarlet pimpernels and expect a good harvest is probably August. If you wait any later than that and your scarlet pimpernels may not have a chance to fully mature. You can get started a little bit earlier by starting your scarlet pimpernels indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Collinsville. You can expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Collinsville may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Collinsville there is a last frost after April 15 so be sure to be ready to cover your scarlet pimpernels in the event of a late frost.

USDA Zone Info for Collinsville

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

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

Plants to Grow in Collinsville

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