One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Troutdale it's a good idea to figure out when it's possible to plant columbine.

Planting Calendar for Columbine

Frost tolerance for columbine:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant columbine a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant columbine in Troutdale 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 columbine and expect a good harvest is probably September. If you wait any later than that and your columbine may not have a chance to really do well. You can get started a few weeks earlier by starting your columbine indoors.

Last Frost Date

The average date of last frost is March 15 in Troutdale. It might get as low as 15°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Troutdale and it will vary from year to year. Since half of the time in Troutdale last frost occurs after March 15 be ready to cover your columbine if you have a surprise late frost.

USDA Zone Info for Troutdale

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 Troutdale

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