One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to estimate when it's possible to plant asters by referring to the USDA zone info for Tustin.

Planting Calendar for Asters

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

Asters do ok in mild cold which tells us that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant asters in Tustin 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. Starting your asters indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Tustin the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Tustin and it will vary from year to year. Half of the time in Tustin there is a last frost after January 31 so make sure that you are prepared to cover your asters in the event of a surprise late frost.

USDA Zone Info for Tustin

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 Tustin

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