Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant calendula in Souderton should be estimated by referring to 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.

You can plant calendula just a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant calendula in Souderton 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. You probably don't want to wait any later than that or else your calendula may not have a chance to fully mature. You can get started a few weeks earlier by starting your calendula indoors.

Last Frost Date

The average date of last frost is April 15 in Souderton. You can expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Souderton and it can change quite a bit from year to year. Since half of the time in Souderton you get a frost after April 15 be ready to protect your calendula in the event of a surprise late frost.

USDA Zone Info for Souderton

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 Souderton

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