One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

A common way of estimating when you can plant astilbe is to examine the USDA zone info for Bath.

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 can survive in very little cold which means that you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant astilbe in Bath 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 grow to maturity. You can get started a little bit earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Bath. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that USDA zone info for Bath is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Bath last frost occurs after April 15 so always be ready to cover your astilbe in the event of a surprise late frost.

USDA Zone Info for Bath

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Bath

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