The USDA Zone info is a great tool for gardeners to help us figure out 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.

The earliest that you can plant asters in San Marino should be estimated by checking out 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 moderately cold tolerant which tells us that you can get them planted earlier than more sensitive plants.

The earliest that you can plant asters in San Marino 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 fully mature. 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 January 31 in San Marino. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for San Marino is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in San Marino you get surprised by a frost after January 31 so make sure that you are ready to protect your asters in the event of a surprise late frost.

USDA Zone Info for San Marino

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 Low	30°F
Highest Expected Low	35°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 San Marino

You may be interested in your other planting guides for San Marino.