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.

In Butler you can determine when it's a good idea to plant periwinkles by reviewing the USDA zone info.

Planting Calendar for Periwinkles

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

You can not plant periwinkles until after all chance of frost has passed because they require warm weather.

The earliest that you can plant periwinkles in Butler 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 grow to maturity. If you are starting your periwinkles indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Butler. In the coldest months of winter you can expect an average low temperature of -10°F.

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

USDA Zone Info for Butler

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 Butler

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