Before planting it is a good idea to find your USDA Zone info to determine your garden 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 Iowa Falls can be estimated by using 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 one of those plants that can tolerate a tiny bit of cold weather which tells us that you can get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant astilbe in Iowa Falls 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. Starting your astilbe indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Iowa Falls. You should expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Iowa Falls and it can change quite a bit from year to year. Half of the time in Iowa Falls it frosts late in the year after April 15 so make sure that you are ready to protect your astilbe if you have one of those late frosts.

USDA Zone Info for Iowa Falls

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Iowa Falls

You may be interested in your other planting guides for Iowa Falls.