The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Monticello can be looked at 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.

You can plant astilbe just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant astilbe in Monticello is April. However, you really should wait until May 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 really do well. You can get started a little bit earlier by starting your astilbe indoors.

Last Frost Date

The average date of last frost is May 15 in Monticello. In the coldest months of winter you should expect an average low temperature of -25°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Monticello and it changes from year to year. Half of the time in Monticello there is a last frost after May 15 so always be ready to protect your astilbe in the event of a late frost.

USDA Zone Info for Monticello

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Monticello

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