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.

The USDA zone info for Lebanon should be read to figure out 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 when the weather gets warmer.

You really shouldn't plant periwinkles until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant periwinkles in Lebanon 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. 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 couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Lebanon. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Lebanon is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Lebanon you get a frost after April 15 so just be sure to be ready to cover your periwinkles in the event of a surprise late frost.

USDA Zone Info for Lebanon

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Lebanon

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