When to Plant Asters in Sebastopol, CA

Before planting it is a good idea to find your USDA Zone info to determine 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.

The first chance to plant asters in Sebastopol should be estimated by using the USDA zone info.


Planting Calendar for Asters

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

Asters are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other frost tender plants.

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

The earliest that you can plant asters in Sebastopol 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 asters and expect a good harvest is probably October. Any later than that and your asters may not have a chance to really do well. Starting your asters indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Sebastopol. In the coldest months of winter you should expect an average low temperature of 20°F.

Always 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 Sebastopol and it can change quite a bit from year to year. Half of the time in Sebastopol you get a frost after February 15 so be sure to be ready to cover your asters if you have one of those late frosts.

USDA Zone Info for Sebastopol

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low20°F
Highest Expected Low25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sebastopol

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