The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Zone 11a you can estimate when it's the best time to plant astilbe by using the USDA zone info.

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 a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant astilbe in Zone 11a is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant astilbe and expect a good harvest is probably November. Any later than that and your astilbe may not have a chance to really do well. If you are starting your astilbe indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Zone 11a it never frosts. You should expect an average low temperature of 40°F in the coldest months of winter.

Since the USDA zone info for Zone 11a is just an average the actual date of last frost is different every year. Since it never frosts in Zone 11a you do not have to be ready to cover your astilbe in the event of a surprise late frost.

USDA Zone Info for Zone 11a

Here is the info for USDA Zone 11a.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	40°F
Highest Expected Low	45°F

This means that on a really cold year, the coldest it will get is 40°F. On most years you should be prepared to experience lows near 45°F.

Plants to Grow in Zone 11a

You may be interested in your other planting guides for Zone 11a.