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.

By looking at the USDA zone info for Niles it's a good idea to estimate when to plant astilbe.

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 mild 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 Niles 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. Starting your astilbe indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Niles. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that USDA zone info for Niles may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Niles you get a frost after April 15 so be sure to be ready to cover your astilbe in the event of a surprise late frost.

USDA Zone Info for Niles

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 Niles

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