When to Plant Asters in Simi Valley, CA

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant asters in Simi Valley should be determined by reviewing 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.

You can plant asters just a bit earlier in the year because they are moderately cold tolerant.

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 Simi Valley 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. You probably don't want to wait any later than that or else your asters may not have a chance to really do well. If you are starting your asters indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Simi Valley the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Simi Valley is an average the actual date of last frost changes from year to year. Since half of the time in Simi Valley there is a last frost after February 15 be ready to protect your asters in the event of one of those late frosts.

USDA Zone Info for Simi Valley

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low25°F
Highest Expected Low30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Simi Valley

You may be interested in your other planting guides for Simi Valley.