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

A common way of determining when it's the best time to plant larkspur is to examine the USDA zone info for Oregon.

Planting Calendar for Larkspur

Frost tolerance for larkspur:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Larkspur can survive in cold weather which means that you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant larkspur in Oregon 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 larkspur and expect a good harvest is probably September. Any later than that and your larkspur may not have a chance to fully mature. You can get started a few weeks earlier by starting your larkspur indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Oregon. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Oregon may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Oregon you get surprised by a frost after April 15 be ready to protect your larkspur in the event of a surprise late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Oregon

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