One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Fountain Hills you should be able to figure out when you can plant periwinkles.

Planting Calendar for Periwinkles

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

Since periwinkles require warm weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant periwinkles in Fountain Hills 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. If you wait any later than that and your periwinkles may not have a chance to really do well. 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

The average date of last frost is February 15 in Fountain Hills. You can expect an average low temperature of 25°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Fountain Hills and it will vary from year to year. Half of the time in Fountain Hills there is a last frost after February 15 so just be sure to be ready to cover your periwinkles in the event of a surprise late frost.

USDA Zone Info for Fountain Hills

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Fountain Hills

You may be interested in your other planting guides for Fountain Hills.