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.

One way of making a decision about when it's possible to plant four-o-clock flower is to look at the USDA zone info for Vista.

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.

You can not plant four-o-clock flower until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant four-o-clock flower in Vista 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 flower and expect a good harvest is probably September. If you wait any later than that and 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

On average the last frost when the weather gets warmer is on January 31 in Vista. In the coldest months of winter you can expect an average low temperature of 30°F.

Just be sure to remember that USDA zone info for Vista is not always accurate and the actual date of last frost is different every year. Since half of the time in Vista there is a last frost after January 31 be ready to cover your four-o-clock flower if you have one of those late frosts.

USDA Zone Info for Vista

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 Vista

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