One of the best tools that you have as gardeners to help us figure out 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.

A way of determining when you can plant watermelon is to consult the USDA zone info for Sonora.

Planting Calendar for Watermelon

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

Since watermelon require warm weather it is necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant watermelon in Sonora 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 watermelon and expect a good harvest is probably September. Any later than that and your watermelon may not have a chance to fully mature. Starting your watermelon indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Sonora. You should expect an average low temperature of 20°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Sonora and it can change quite a bit from year to year. Half of the time in Sonora you get a frost after February 15 so make sure that you are ready to protect your watermelon in the event of a late frost.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sonora

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