One of the first steps you take when you are getting a good idea 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.

The earliest that you can plant hardy asters in Imperial should be estimated by checking out the USDA zone info.

Planting Calendar for Hardy Asters

Frost tolerance for hardy asters:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

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

The earliest that you can plant hardy asters in Imperial is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant hardy asters and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hardy asters may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your hardy asters indoors.

Last Frost Date

On average the last frost is on January 31 in Imperial. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Imperial is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Imperial you get a frost after January 31 be ready to cover your hardy asters in the event of a late frost.

USDA Zone Info for Imperial

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 Imperial

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