One of the first steps you take when you are making a decision about 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 USDA zone info for Wasco should be read to determine when you can plant petunias.

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 tend to make it in very little cold which tells us 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 Wasco 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. Any later than that and your petunias may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your petunias indoors.

Last Frost Date

The average date of last frost is February 15 in Wasco. In the coldest months of winter you should expect an average low temperature of 20°F.

Since the USDA zone info for Wasco may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Wasco last frost occurs after February 15 so be sure to be ready to cover your petunias in the event of one of those late frosts.

USDA Zone Info for Wasco

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 Wasco

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