The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Sheldon you can estimate when it's a good idea to plant calendula 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.

Since calendula are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant calendula in Sheldon 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. You probably don't want to wait any later than that or else 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

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

It's important to remember that USDA zone info for Sheldon is not always accurate and the actual date of last frost changes from year to year. Half of the time in Sheldon you get surprised by a frost after May 15 so make sure that you are ready to cover your calendula if you have a surprise late frost.

USDA Zone Info for Sheldon

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 Sheldon

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