One of the first steps you take when you are estimating your gardening schedule is find your 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.

In Lebanon you can determine when it's possible to plant periwinkles by referring to the USDA zone info.

Planting Calendar for Periwinkles

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

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

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. Any later than that and your periwinkles may not have a chance to grow to maturity. If you are starting your periwinkles indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Lebanon is just an average the actual date of last frost will vary from year to year. Half of the time in Lebanon you get surprised by a frost after April 15 so just be sure to be ready to protect your periwinkles in the event of a surprise late frost.

USDA Zone Info for Lebanon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Lebanon

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