The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's the best time to plant periwinkles in Casa Grande 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.

It's probably not a good idea to plant periwinkles until after the last frost because they are not cold tolerant.

The earliest that you can plant periwinkles in Casa Grande 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 fully mature. Starting your periwinkles indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Casa Grande. You should expect an average low temperature of 5°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Casa Grande and it changes from year to year. Since half of the time in Casa Grande it frosts late in the year after April 15 be ready to protect your periwinkles in the event of one of those late frosts.

USDA Zone Info for Casa Grande

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Casa Grande

You may be interested in your other planting guides for Casa Grande.