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

In Rio Grande City you can determine when to plant petunias by referring to 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 do ok in mild cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant petunias in Rio Grande City 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. Starting your petunias indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Rio Grande City. It might get as low as 25°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Rio Grande City and it changes from year to year. Half of the time in Rio Grande City there is a last frost after February 15 so always be ready to protect your petunias in the event of a surprise late frost.

USDA Zone Info for Rio Grande City

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 Rio Grande City

You may be interested in your other planting guides for Rio Grande City.