When to Plant Periwinkles in Bethalto, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant periwinkles in Bethalto can be determined by reviewing the USDA zone info.


Planting Calendar for Periwinkles

Frost tolerance for periwinkles: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Since periwinkles do not do well in cold weather it is necessary to wait until after the last frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant periwinkles
Possibly ok, but a risky time to plant periwinkles
Probably not a good time to plant periwinkles

The earliest that you can plant periwinkles in Bethalto 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 periwinkles and expect a good harvest is probably August. Any later than that and your periwinkles may not have a chance to really do well. You can get started a little bit earlier by starting your periwinkles indoors.

Last Frost Date

In Bethalto the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Bethalto is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Bethalto it frosts late in the year after April 15 be ready to protect your periwinkles if you have a surprise late frost.

USDA Zone Info for Bethalto

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 Bethalto

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