When to Plant Four O' Clock in Zone 3b

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Zone 3b it's a good idea to determine when it's a good idea to plant four o' clock.


Planting Calendar for Four O' Clock

Frost tolerance for four o' clock: Not tolerant of frost.
When to plant: After the last frost.

Since four o' clock are not cold tolerant you need to wait until after the last frost when the weather gets warmer before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant four o' clock
Possibly ok, but a risky time to plant four o' clock
Probably not a good time to plant four o' clock

The earliest that you can plant four o' clock 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 four o' clock and expect a good harvest is probably August. You probably don't want to wait any later than that or else your four o' clock may not have a chance to fully mature. Starting your four o' clock indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Zone 3b is an average and the actual date of last frost will vary from year to year. Since half of the time in Zone 3b you get a frost after May 15 be ready to protect your four o' clock in the event of 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.