One of the first steps you take when you are getting a good idea 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 getting a good idea when it's the best time to plant calendula is to use the USDA zone info for Elk River.

Planting Calendar for Calendula

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

Since calendula are moderately cold tolerant you can plant them a little earlier in the year than other frost tender plants.

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

The last month that you can plant calendula and expect a good harvest is probably August. If you wait any later than that and your calendula may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your calendula indoors.

Last Frost Date

In Elk River the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -25°F.

Just be sure to remember that USDA zone info for Elk River is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Elk River you get a frost after May 15 be ready to cover your calendula if you have a surprise late frost.

USDA Zone Info for Elk River

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Elk River

You may be interested in your other planting guides for Elk River.