One of the first steps you take when you are making a decision about 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.

The USDA zone info for Arnold should be reffered to in order to estimate when it's the best time 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 has passed.

Four O' Clock do not do well in cold weather which means that you have to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant four o' clock in Arnold 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. You can get started a little bit earlier by starting your four o' clock indoors.

Last Frost Date

In Arnold the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Arnold and it will vary from year to year. Since half of the time in Arnold you get a frost after April 15 be ready to protect your four o' clock if you have one of those late frosts.

USDA Zone Info for Arnold

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Arnold

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