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

A common way of figuring out when to plant four o' clock is to consult the USDA zone info for Fairfax.

Planting Calendar for Four O' Clock

Frost tolerance for four o' clock:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since four o' clock are not cold tolerant it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant four o' clock in Fairfax 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 four o' clock and expect a good harvest is probably September. You probably don't want to wait any later than that or else your four o' clock may not have a chance to really do well. If you are starting your four o' clock indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Fairfax. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Fairfax is an average the actual date of last frost will vary from year to year. Since half of the time in Fairfax last frost occurs after February 15 be ready to protect your four o' clock in the event of a late frost.

USDA Zone Info for Fairfax

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Fairfax

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