One of the first steps you take when you are estimating 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 best time to plant four-o-clock flower in Roma should be estimated by looking at the USDA zone info.

Planting Calendar for Four-o-clock flower

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

It's a bad idea to plant four-o-clock flower until after the last frost has passed because they require warm weather.

The earliest that you can plant four-o-clock flower in Roma 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 flower 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 flower may not have a chance to grow to maturity. Starting your four-o-clock flower indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Roma. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Roma is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Roma it frosts late in the year after February 15 so make sure that you are ready to cover your four-o-clock flower if you have one of those late frosts.

USDA Zone Info for Roma

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 Roma

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