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

The earliest that you can plant calendula in Winona should be estimated by using 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.

Calendula are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than plants that are more sensitive to the cold.

The earliest that you can plant calendula in Winona 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 grow to maturity. 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

The average date of last frost is May 15 in Winona. It might get as low as -25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Winona and it changes from year to year. Half of the time in Winona it frosts late in the year after May 15 so make sure that you are prepared to cover your calendula in the event of a late frost.

USDA Zone Info for Winona

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 Winona

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