One of the best tools that you have as gardeners to help us figure out 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.

By using the USDA zone info for Hillsdale you should be able to estimate when it's possible to plant calendula.

Planting Calendar for Calendula

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

Calendula tend to make it in a little bit of cold which means that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant calendula in Hillsdale 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. If you are starting your calendula indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Hillsdale. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Hillsdale may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Hillsdale last frost occurs after April 15 so be sure to be ready to cover your calendula in the event of one of those late frosts.

USDA Zone Info for Hillsdale

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Hillsdale

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