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.

The earliest that you can plant calendula in Clarks Summit can be determined by reviewing the USDA zone info.

Planting Calendar for Calendula

Frost tolerance for calendula:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Calendula are moderately cold tolerant which tells us that you can plant them a little bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant calendula in Clarks Summit is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant calendula and expect a good harvest is probably September. Any later than that and your calendula may not have a chance to really do well. Starting your calendula indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Clarks Summit. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Clarks Summit is not always accurate the actual date of last frost will vary from year to year. Half of the time in Clarks Summit you get surprised by a frost after April 15 so make sure that you are ready to cover your calendula in the event of a surprise late frost.

USDA Zone Info for Clarks Summit

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Clarks Summit

You may be interested in your other planting guides for Clarks Summit.