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

One way of estimating when to plant periwinkles is to check out the USDA zone info for Wickenburg.

Planting Calendar for Periwinkles

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

You should not plant periwinkles until after the last frost when the weather gets warmer because they do not do well in cold weather.

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

Last Frost Date

The average date of last frost is February 15 in Wickenburg. In the coldest months of winter you should expect an average low temperature of 20°F.

Since the USDA zone info for Wickenburg may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Wickenburg you get a frost after February 15 be ready to cover your periwinkles in the event of a late frost.

USDA Zone Info for Wickenburg

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Wickenburg

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