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.

You can figure out when it's possible to plant watermelon in San Jose by referring to the USDA zone info.

Planting Calendar for Watermelon

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

Since watermelon are not cold tolerant it is important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant watermelon in San Jose 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. You probably don't want to wait any later than that or else your watermelon may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your watermelon indoors.

Last Frost Date

The average date of last frost is February 15 in San Jose. It might get as low as 25°F during the coldest months of winter.

Remember that USDA zone info for San Jose is just an average and the actual date of last frost is different every year. Half of the time in San Jose it frosts late in the year after February 15 so just be sure to be ready to protect your watermelon in the event of a late frost.

USDA Zone Info for San Jose

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 San Jose

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