Before planting it is a good idea to find your USDA Zone info to figure out 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.

By referring to the USDA zone info for Waunakee it's a good idea 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 get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant delphinium in Waunakee 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 grow to maturity. Starting your delphinium indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Waunakee. You can expect an average low temperature of -20°F in the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Waunakee and it is different every year. Half of the time in Waunakee it frosts late in the year after April 15 so make sure that you are prepared to protect your delphinium in the event of a late frost.

USDA Zone Info for Waunakee

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

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

Plants to Grow in Waunakee

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