One of the first steps you take when you are determining 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 USDA zone info for Bristol should be used to estimate when it's possible to plant astilbe.

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 tend to make it in very little 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 astilbe in Bristol 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. You probably don't want to wait any later than that or else your astilbe may not have a chance to fully mature. You can get started a little bit earlier by starting your astilbe indoors.

Last Frost Date

In Bristol the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Remember that USDA zone info for Bristol is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Bristol you get a frost after April 15 so just be sure to be ready to cover your astilbe in the event of one of those late frosts.

USDA Zone Info for Bristol

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Bristol

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