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.

In Winona you can figure out when it's a good idea to plant osteospermum by using the USDA zone info.

Planting Calendar for Osteospermum

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

Osteospermum are moderately cold tolerant which tells us that you can plant them earlier than more sensitive plants.

The earliest that you can plant osteospermum 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 osteospermum and expect a good harvest is probably August. Any later than that and your osteospermum may not have a chance to fully mature. If you are starting your osteospermum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Winona is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Winona it frosts late in the year after May 15 be ready to protect your osteospermum if you have one of those late frosts.

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.