One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of estimating when to plant four o' clock is to examine the USDA zone info for Downingtown.

Planting Calendar for Four O' Clock

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

Four O' Clock require warm weather which tells us that you have 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 Downingtown 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. Any later than that and 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Downingtown. In the coldest months of winter you should expect an average low temperature of -5°F.

Keep in mind that USDA zone info for Downingtown is an average and the actual date of last frost will vary from year to year. Half of the time in Downingtown there is a last frost after April 15 so make sure that you are ready to protect your four o' clock in the event of a late frost.

USDA Zone Info for Downingtown

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Downingtown

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