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.

It's possible to figure out when to plant four o' clock by using the USDA zone info for Upland.

Planting Calendar for Four O' Clock

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

Four O' Clock require warm weather which tells us that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant four o' clock in Upland is February. However, you really should wait until March 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 fully mature. You can get started a little bit earlier by starting your four o' clock indoors.

Last Frost Date

On average all chance of frost has passed is on January 31 in Upland. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Upland is an average the actual date of last frost is different every year. Half of the time in Upland last frost occurs after January 31 so make sure that you are prepared to protect your four o' clock in the event of one of those late frosts.

USDA Zone Info for Upland

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

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

Plants to Grow in Upland

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