One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when it's the best time to plant osteospermum is to look at the USDA zone info for Donora.

Planting Calendar for Osteospermum

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

Since osteospermum are one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant osteospermum in Donora 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. You can get started a little bit earlier by starting your osteospermum indoors.

Last Frost Date

In Donora the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Donora is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Donora it frosts late in the year after April 15 be ready to cover your osteospermum in the event of one of those late frosts.

USDA Zone Info for Donora

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Donora

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