One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when you can plant periwinkles in Siloam Springs by checking out the USDA zone info.

Planting Calendar for Periwinkles

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

You can not plant periwinkles until after all chance of frost has passed because they require warm weather.

The earliest that you can plant periwinkles in Siloam Springs 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 really do well. Starting your periwinkles indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Siloam Springs the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 0°F.

Since the USDA zone info for Siloam Springs is not always accurate the actual date of last frost changes from year to year. Since half of the time in Siloam Springs you get surprised by a frost after April 15 be ready to cover your periwinkles if you have one of those late frosts.

USDA Zone Info for Siloam Springs

Here is the info for USDA Zone 7a.

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

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Siloam Springs

You may be interested in your other planting guides for Siloam Springs.