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 common way of getting a good idea when it's possible to plant astilbe is to consult the USDA zone info for South San Francisco.

Planting Calendar for Astilbe

Frost tolerance for astilbe:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant astilbe slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant astilbe in South San Francisco 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 astilbe and expect a good harvest is probably September. If you wait any later than that and your astilbe may not have a chance to grow to maturity. Starting your astilbe indoors is a great way to get them started a little bit earlier.

Last Frost Date

In South San Francisco the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Remember that USDA zone info for South San Francisco may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in South San Francisco you get surprised by a frost after January 31 so make sure that you are ready to cover your astilbe in the event of a late frost.

USDA Zone Info for South San Francisco

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in South San Francisco

You may be interested in your other planting guides for South San Francisco.