One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Los Altos you can estimate when it's the best time to plant marigold by checking out the USDA zone info.

Planting Calendar for Marigold

Frost tolerance for marigold:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You can not plant marigold until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant marigold in Los Altos 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 marigold and expect a good harvest is probably September. You probably don't want to wait any later than that or else your marigold may not have a chance to really do well. If you are starting your marigold indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Los Altos the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Los Altos and it will vary from year to year. Since half of the time in Los Altos it frosts late in the year after February 15 be ready to cover your marigold 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.