When to Plant Asters in Monrovia, CA

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant asters in Monrovia 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 Monrovia 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 fully mature. You can get started a couple of weeks earlier by starting your asters indoors.

Last Frost Date

The average date of last frost is January 31 in Monrovia. In the coldest months of winter you should expect an average low temperature of 30°F.

Just be sure to remember that USDA zone info for Monrovia 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 Monrovia you get surprised by a frost after January 31 so just be sure to be ready to protect your asters in the event of one of those late frosts.

USDA Zone Info for Monrovia

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 Monrovia

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