Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of making a decision about when it's a good idea to plant osteospermum is to examine the USDA zone info for Alpharetta.

Planting Calendar for Osteospermum

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

Osteospermum can survive in moderate cold which means that 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 Alpharetta 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. Any later than that and 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 Alpharetta the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Alpharetta and it will vary from year to year. Since half of the time in Alpharetta you get surprised by a frost after April 15 be ready to cover your osteospermum in the event of one of those late frosts.

USDA Zone Info for Alpharetta

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Alpharetta

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