The USDA Zone info is a great tool for gardeners to help us determine 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.

The first opportunity to plant celosia in Zone 4b can be figured out by looking at the USDA zone info.

Planting Calendar for Celosia

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

Since celosia do not do well in cold weather it is important to wait until after the last frost before you can plant them.

The earliest that you can plant celosia in Zone 4b 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 celosia and expect a good harvest is probably August. If you wait any later than that and your celosia may not have a chance to really do well. Starting your celosia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Zone 4b. In the coldest months of winter you should expect an average low temperature of -25°F.

Remember that USDA zone info for Zone 4b is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Zone 4b you get a frost after May 15 be ready to protect your celosia if you have a late frost.

USDA Zone Info for Zone 4b

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 Zone 4b

You may be interested in your other planting guides for Zone 4b.