One of the first steps you take when you are figuring out 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.

One way of estimating when to plant calendula is to refer to the USDA zone info for Dover.

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 a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant calendula in Dover 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 really do well. Starting your calendula indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Dover. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Dover is just an average the actual date of last frost is different every year. Since half of the time in Dover there is a last frost after April 15 be ready to protect your calendula if you have a late frost.

USDA Zone Info for Dover

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 Dover

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