One of the best tools that you have as gardeners to help us estimate 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 Madison you can figure out when to plant osteospermum by referring to 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 do well in moderate cold which tells us that you can plant them a little bit earlier than other frost tender plants.

The earliest that you can plant osteospermum in Madison 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 osteospermum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your osteospermum may not have a chance to grow to maturity. If you are starting your osteospermum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Madison the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Madison and it changes from year to year. Half of the time in Madison you get surprised by a frost after March 15 so be sure to be ready to cover your osteospermum in the event of a surprise late frost.

USDA Zone Info for Madison

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Madison

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