One of the first steps you take when you are determining your gardening schedule is find your 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.

In Ashtabula you can estimate when to plant astilbe 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 are barely cold tolerant which tells us that you can start planting them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Ashtabula 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 really do well. If you are starting your astilbe indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Ashtabula. You can expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Ashtabula is just an average and the actual date of last frost will vary from year to year. Half of the time in Ashtabula you get surprised by a frost after April 15 so make sure that you are prepared to protect your astilbe in the event of one of those late frosts.

USDA Zone Info for Ashtabula

Here is the info for USDA Zone 6b.

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

Plants to Grow in Ashtabula

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