One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when it's possible to plant asters by looking at the USDA zone info for Walnut.

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 plant them a little bit earlier than other frost tender plants.

The earliest that you can plant asters in Walnut 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. If you wait any later than that and your asters may not have a chance to really do well. 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 Walnut. In the coldest months of winter you should expect an average low temperature of 30°F.

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

USDA Zone Info for Walnut

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 Walnut

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