One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for San Luis you will be able to determine when to plant marigold.

Planting Calendar for Marigold

Frost tolerance for marigold:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant marigold until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant marigold in San Luis 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 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 grow to maturity. If you are starting your marigold indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in San Luis. It might get as low as 30°F during the coldest months of winter.

Always keep in mind that USDA zone info for San Luis is just an average and the actual date of last frost will vary from year to year. Half of the time in San Luis you get surprised by a frost after January 31 so always be ready to protect your marigold in the event of a surprise late frost.

USDA Zone Info for San Luis

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 San Luis

You may be interested in your other planting guides for San Luis.