One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

You will be able to figure out when to plant calendula by looking at the USDA zone info for Roxboro.

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 earlier in the year because they are moderately cold tolerant.

The earliest that you can plant calendula in Roxboro 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. If you wait any later than that and your calendula may not have a chance to grow to maturity. Starting your calendula indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Roxboro. In the coldest months of winter you should expect an average low temperature of 5°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Roxboro and it changes from year to year. Half of the time in Roxboro you get surprised by a frost after April 15 so always be ready to protect your calendula in the event of a surprise late frost.

USDA Zone Info for Roxboro

Here is the info for USDA Zone 7b.

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

Plants to Grow in Roxboro

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