Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In San Juan you can figure out when you can plant petunias by checking out the USDA zone info.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Petunias are barely cold tolerant which means that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant petunias in San Juan 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 petunias and expect a good harvest is probably September. You probably don't want to wait any later than that or else your petunias may not have a chance to fully mature. If you are starting your petunias indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in San Juan. You should expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for San Juan is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in San Juan you get a frost after February 15 so always be ready to protect your petunias in the event of a surprise late frost.

USDA Zone Info for San Juan

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 Juan

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