One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

You can determine when it's possible to plant delphinium in Leavenworth by using the USDA zone info.

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 do ok in moderate cold which means that you can get them planted just a bit earlier than other plants that might not handle the cold.

The earliest that you can plant delphinium in Leavenworth 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. You probably don't want to wait any later than that or else your delphinium may not have a chance to really do well. You can get started a few weeks earlier by starting your delphinium indoors.

Last Frost Date

The average date of last frost is April 15 in Leavenworth. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Leavenworth is just an average the actual date of last frost will vary from year to year. Half of the time in Leavenworth you get surprised by a frost after April 15 so just be sure to be ready to protect your delphinium if you have a late frost.

USDA Zone Info for Leavenworth

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Leavenworth

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