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

One way of figuring out when to plant napa valley fern is to use the USDA zone info for Zone 3b.

Planting Calendar for Napa Valley Fern

Frost tolerance for napa valley fern:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's probably not a good idea to plant napa valley fern until after the last frost has passed because they require warm weather.

The earliest that you can plant napa valley fern in Zone 3b is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant napa valley fern and expect a good harvest is probably August. You probably don't want to wait any later than that or else your napa valley fern may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your napa valley fern indoors.

Last Frost Date

In Zone 3b the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -35°F.

Since the USDA zone info for Zone 3b is an average the actual date of last frost will vary from year to year. Half of the time in Zone 3b there is a last frost after May 15 so make sure that you are ready to cover your napa valley fern if you have one of those late frosts.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in your other planting guides for Zone 3b.