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.

The USDA zone info for North Salt Lake should be reviewed to determine when it's the best time to 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 because they do not do well in cold weather.

The earliest that you can plant periwinkles in North Salt Lake 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 couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in North Salt Lake. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for North Salt Lake is just an average the actual date of last frost is different every year. Half of the time in North Salt Lake you get surprised by a frost after April 15 so always be ready to cover your periwinkles if you have a late frost.

USDA Zone Info for North Salt Lake

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 North Salt Lake

You may be interested in your other planting guides for North Salt Lake.