Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Issaquah should be used to estimate when it's the best time to plant oenothera.

Planting Calendar for Oenothera

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

Oenothera are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than more sensitive plants.

The earliest that you can plant oenothera in Issaquah 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 really do well. Starting your oenothera indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Issaquah. In the coldest months of winter you should expect an average low temperature of 15°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Issaquah and it changes from year to year. Half of the time in Issaquah you get a frost after March 15 so always be ready to protect your oenothera in the event of a late frost.

USDA Zone Info for Issaquah

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 Issaquah

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