The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's a good idea to plant flower-of-an-hour in Rialto by checking out the USDA zone info.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Flower-of-an-Hour do ok in some cold which means that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant flower-of-an-hour in Rialto 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 flower-of-an-hour and expect a good harvest is probably September. If you wait any later than that and your flower-of-an-hour may not have a chance to grow to maturity. Starting your flower-of-an-hour indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Rialto the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for Rialto is not always accurate the actual date of last frost is different every year. Since half of the time in Rialto last frost occurs after January 31 be ready to protect your flower-of-an-hour in the event of a surprise late frost.

USDA Zone Info for Rialto

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 Rialto

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