Before planting it is a good idea to find your USDA Zone info to estimate 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.

A common way of estimating when it's a good idea to plant periwinkles is to refer to the USDA zone info for Hempstead.

Planting Calendar for Periwinkles

Frost tolerance for periwinkles:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since periwinkles are not cold tolerant it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant periwinkles in Hempstead 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. You probably don't want to wait any later than that or else your periwinkles may not have a chance to grow to maturity. Starting your periwinkles indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Hempstead the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Hempstead and it can change quite a bit from year to year. Since half of the time in Hempstead it frosts late in the year after February 15 be ready to protect your periwinkles in the event of a late frost.

USDA Zone Info for Hempstead

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 Hempstead

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