The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's the best time to plant astilbe in Oak Ridge by looking at the USDA zone info.

Planting Calendar for Astilbe

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

Astilbe do ok in moderate cold which means that you can get them planted just a bit earlier than other plants that might not handle the cold.

The earliest that you can plant astilbe in Oak Ridge 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 astilbe and expect a good harvest is probably August. Any later than that and your astilbe may not have a chance to really do well. You can get started a few weeks earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Oak Ridge. You should expect an average low temperature of 5°F in the coldest months of winter.

Always keep in mind that USDA zone info for Oak Ridge may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Oak Ridge you get a frost after April 15 so be sure to be ready to cover your astilbe if you have a surprise late frost.

USDA Zone Info for Oak Ridge

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Oak Ridge

You may be interested in your other planting guides for Oak Ridge.