Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant astilbe in Ketchikan can be figured out 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.

Since astilbe are barely cold tolerant you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Ketchikan 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. If you wait 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

On average the last frost is on April 15 in Ketchikan. It might get as low as 5°F during the coldest months of winter.

Remember that USDA zone info for Ketchikan is just an average and the actual date of last frost will vary from year to year. Half of the time in Ketchikan you get surprised by a frost after April 15 so make sure that you are ready to cover your astilbe if you have a surprise late frost.

USDA Zone Info for Ketchikan

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Ketchikan

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