Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant petunias in Snoqualmie can be estimated 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.

Since petunias are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant petunias in Snoqualmie 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 petunias and expect a good harvest is probably August. If you wait any later than that and your petunias may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your petunias indoors.

Last Frost Date

In Snoqualmie the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

Since the USDA zone info for Snoqualmie may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Snoqualmie you get surprised by a frost after March 15 so just be sure to be ready to protect your petunias if you have a surprise late frost.

USDA Zone Info for Snoqualmie

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Snoqualmie

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