One of the first steps you take when you are getting a good idea your gardening schedule is find your 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 first opportunity to plant osteospermum in Green River can be figured out 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 ok in a little bit of cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant osteospermum in Green River 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. You can get started a couple of weeks earlier by starting your osteospermum indoors.

Last Frost Date

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

Since the USDA zone info for Green River may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Green River last frost occurs after May 15 so make sure that you are ready to cover your osteospermum if you have a surprise late frost.

USDA Zone Info for Green River

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 Green River

You may be interested in your other planting guides for Green River.