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.

In Los Altos you can estimate when to plant flower-of-an-hour by using 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 are barely cold tolerant which tells us that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant flower-of-an-hour in Los Altos 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. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to really do well. You can get started a couple of weeks earlier by starting your flower-of-an-hour indoors.

Last Frost Date

On average the last frost is on February 15 in Los Altos. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Los Altos is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Los Altos you get a frost after February 15 so always be ready to protect your flower-of-an-hour if you have a late frost.

USDA Zone Info for Los Altos

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 Los Altos

You may be interested in your other planting guides for Los Altos.