The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Wasco you can determine when it's the best time to plant dahlias by using the USDA zone info.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's a bad idea to plant dahlias until after all chance of frost has passed because they require warm weather.

The earliest that you can plant dahlias in Wasco 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 dahlias and expect a good harvest is probably September. Any later than that and your dahlias may not have a chance to fully mature. You can get started a little bit earlier by starting your dahlias indoors.

Last Frost Date

In Wasco the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Wasco and it is different every year. Since half of the time in Wasco there is a last frost after February 15 be ready to cover your dahlias if you have a surprise late frost.

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.