The USDA Zone info is a great tool for gardeners to help us determine 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.

By checking out the USDA zone info for Woodinville you should be able to determine when you can plant delphinium.

Planting Calendar for Delphinium

Frost tolerance for delphinium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Delphinium are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant delphinium in Woodinville 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 delphinium and expect a good harvest is probably August. Any later than that and your delphinium may not have a chance to fully mature. If you are starting your delphinium indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Woodinville and it will vary from year to year. Half of the time in Woodinville you get surprised by a frost after March 15 so always be ready to cover your delphinium in the event of a late frost.

USDA Zone Info for Woodinville

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 Woodinville

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