One of the best tools that you have as gardeners to help us estimate 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.

The USDA zone info for Snohomish can be looked at to figure out when you can plant cardinal flower.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Cardinal Flower do not do well in cold weather which means that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant cardinal flower in Snohomish is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant cardinal flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cardinal flower may not have a chance to fully mature. Starting your cardinal flower indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Snohomish. You should expect an average low temperature of 15°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Snohomish and it will vary from year to year. Since half of the time in Snohomish you get surprised by a frost after March 15 be ready to cover your cardinal flower if you have one of those late frosts.

USDA Zone Info for Snohomish

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 Snohomish

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