The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant astilbe in Norwalk can be determined by referring to 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 tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant astilbe in Norwalk 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. If you wait any later than that and your astilbe may not have a chance to grow to maturity. If you are starting your astilbe indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Norwalk. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Norwalk and it is different every year. Half of the time in Norwalk you get surprised by a frost after April 15 so make sure that you are prepared to cover your astilbe if you have one of those late frosts.

USDA Zone Info for Norwalk

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 Norwalk

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