One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 determine when it's a good idea to plant hardy asters by looking at the USDA zone info for Warrenton.

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 are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant hardy asters in Warrenton 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 really do well. You can get started a couple of weeks earlier by starting your hardy asters indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Warrenton. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Warrenton is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Warrenton there is a last frost after February 15 so be sure to be ready to protect your hardy asters if you have a surprise late frost.

USDA Zone Info for Warrenton

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 Warrenton

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