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.

One way of getting a good idea when you can plant marigold is to refer to the USDA zone info for Alamo.

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 a bad idea to plant marigold until after the last frost because they are not cold tolerant.

The earliest that you can plant marigold in Alamo 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. Any later than that and your marigold may not have a chance to fully mature. 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

The average date of last frost is February 15 in Alamo. In the coldest months of winter you should expect an average low temperature of 25°F.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Alamo and it can change quite a bit from year to year. Half of the time in Alamo you get surprised by a frost after February 15 so make sure that you are ready to protect your marigold if you have a surprise late frost.

USDA Zone Info for Alamo

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 Alamo

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