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

A way of determining when you can plant four o' clock is to use the USDA zone info for Lake Forest.

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 require warm weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant four o' clock in Lake Forest is April. However, you really should wait until May 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 grow to maturity. Starting your four o' clock indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Lake Forest. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Lake Forest may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Lake Forest last frost occurs after April 15 be ready to protect your four o' clock in the event of a late frost.

USDA Zone Info for Lake Forest

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Lake Forest

You may be interested in your other planting guides for Lake Forest.