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.

A way of estimating when to plant osteospermum is to check out the USDA zone info for Douglas.

Planting Calendar for Osteospermum

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

Osteospermum do ok in moderate cold which means that you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant osteospermum in Douglas 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. If you wait any later than that and your osteospermum may not have a chance to really do well. You can get started a little bit earlier by starting your osteospermum indoors.

Last Frost Date

In Douglas the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Douglas and it changes from year to year. Since half of the time in Douglas you get a frost after May 15 be ready to cover your osteospermum if you have one of those late frosts.

USDA Zone Info for Douglas

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 Douglas

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