One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Youngsville it's a good idea 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.

It's not a good idea to plant periwinkles until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant periwinkles in Youngsville 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 really do well. You can get started a couple of weeks earlier by starting your periwinkles indoors.

Last Frost Date

In Youngsville 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.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Youngsville and it can change quite a bit from year to year. Half of the time in Youngsville last frost occurs after February 15 so make sure that you are ready to protect your periwinkles if you have a surprise late frost.

USDA Zone Info for Youngsville

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 Youngsville

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