One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when you can plant astilbe in Forest Park 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 means that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Forest Park 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. 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

On average the last frost is on April 15 in Forest Park. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Forest Park may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Forest Park last frost occurs after April 15 so just be sure to be ready to cover your astilbe if you have a late frost.

USDA Zone Info for Forest Park

Here is the info for USDA Zone 6a.

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

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Forest Park

You may be interested in your other planting guides for Forest Park.