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

A common way of estimating when you can plant periwinkles is to consult the USDA zone info for Smithville.

Planting Calendar for Periwinkles

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

It's not a good idea to plant periwinkles until after the last frost because they require warm weather.

The earliest that you can plant periwinkles in Smithville 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. You can get started a few weeks earlier by starting your periwinkles indoors.

Last Frost Date

The average date of last frost is March 15 in Smithville. It might get as low as 15°F during the coldest months of winter.

Keep in mind that USDA zone info for Smithville is an average and the actual date of last frost will vary from year to year. Since half of the time in Smithville you get surprised by a frost after March 15 be ready to cover your periwinkles in the event of a late frost.

USDA Zone Info for Smithville

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Smithville

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