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.

A way of figuring out when it's the best time to plant astilbe is to look at the USDA zone info for Lebanon.

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 plant them slightly earlier than more sensitive plants.

The earliest that you can plant astilbe in Lebanon 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 grow to maturity. You can get started a few weeks earlier by starting your astilbe indoors.

Last Frost Date

In Lebanon the average date of last frost happens on April 15. You can expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Lebanon is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Lebanon you get surprised by a frost after April 15 so always be ready to protect your astilbe if you have a late frost.

USDA Zone Info for Lebanon

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 Lebanon

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