One of the first steps you take when you are figuring out 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.

You can determine when it's possible to plant hardy asters in Spokane by referring to 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 moderate cold which tells us that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant hardy asters in Spokane is March. However, you really should wait until April 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 August. Any later than that and your hardy asters may not have a chance to fully mature. Starting your hardy asters indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Spokane. You should expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Spokane is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Spokane last frost occurs after April 15 be ready to protect your hardy asters if you have one of those late frosts.

USDA Zone Info for Spokane

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Spokane

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