When to Plant Astilbe in Union City, CA

One of the first steps you take when you are estimating 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.

One way of getting a good idea when it's a good idea to plant astilbe is to look at the USDA zone info for Union City.


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.

Since astilbe are barely cold tolerant you can plant them slightly earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant astilbe
Possibly ok, but a risky time to plant astilbe
Probably not a good time to plant astilbe

The earliest that you can plant astilbe in Union City 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 fully mature. You can get started a little bit earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in Union City. In the coldest months of winter you can expect an average low temperature of 30°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Union City and it is different every year. Half of the time in Union City there is a last frost after January 31 so make sure that you are ready to protect your astilbe in the event of a surprise late frost.

USDA Zone Info for Union City

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 Low30°F
Highest Expected Low35°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 Union City

You may be interested in your other planting guides for Union City.