One of the best tools that you have as gardeners to help us figure out 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 figure out when it's a good idea to plant delphinium in Grants Pass by looking at 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 are barely cold tolerant which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant delphinium in Grants Pass 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

The average date of last frost is March 15 in Grants Pass. You can expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Grants Pass is an average the actual date of last frost will vary from year to year. Half of the time in Grants Pass there is a last frost after March 15 so just be sure to be ready to protect your delphinium in the event of a late frost.

USDA Zone Info for Grants Pass

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	October 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 Grants Pass

You may be interested in your other planting guides for Grants Pass.