One of the first steps you take when you are determining 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 Snoqualmie can be looked at to estimate when you can plant oenothera.

Planting Calendar for Oenothera

Frost tolerance for oenothera:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since oenothera are moderately cold tolerant you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant oenothera in Snoqualmie 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 oenothera and expect a good harvest is probably September. Any later than that and your oenothera may not have a chance to grow to maturity. Starting your oenothera indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Snoqualmie and it changes from year to year. Since half of the time in Snoqualmie it frosts late in the year after March 15 be ready to cover your oenothera in the event of 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.