One of the first steps you take when you are figuring out your gardening schedule is find your 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.

The earliest that you can plant petunias in Williams can be figured out by using 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 a tiny bit of cold which means that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant petunias in Williams 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 grow to maturity. Starting your petunias indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Williams the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Williams and it will vary from year to year. Since half of the time in Williams you get surprised by a frost after February 15 be ready to protect your petunias if you have a late frost.

USDA Zone Info for Williams

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 Williams

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