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.

By checking out the USDA zone info for Kingfisher it's a good idea to figure out when you can plant periwinkles.

Planting Calendar for Periwinkles

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

You really shouldn't plant periwinkles until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant periwinkles in Kingfisher 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. If you wait 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 couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Kingfisher. You can expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Kingfisher is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Kingfisher it frosts late in the year after April 15 so make sure that you are prepared to cover your periwinkles in the event of a surprise late frost.

USDA Zone Info for Kingfisher

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 Kingfisher

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