One of the best tools that you have as gardeners to help us determine 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.

The first chance to plant astilbe in Gardiner should 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 do well in very little cold which tells us 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 Gardiner 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 couple of weeks earlier.

Last Frost Date

In Gardiner the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

It's important to remember that USDA zone info for Gardiner is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Gardiner it frosts late in the year after April 15 so make sure that you are prepared to protect your astilbe if you have a surprise late frost.

USDA Zone Info for Gardiner

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 Gardiner

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