Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Ukiah it's possible to figure out when it's the best time to plant asters.

Planting Calendar for Asters

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

Since asters are moderately cold tolerant you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant asters in Ukiah 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. Starting your asters indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Ukiah. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Ukiah is not always accurate the actual date of last frost will vary from year to year. Half of the time in Ukiah you get surprised by a frost after February 15 so make sure that you are ready to cover your asters in the event of a late frost.

USDA Zone Info for Ukiah

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Ukiah

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