The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Silverton it's possible to estimate 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.

Since columbine do well in moderate cold you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant columbine in Silverton 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. Any later than that and your columbine may not have a chance to grow to maturity. Starting your columbine indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Silverton the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Silverton is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Silverton there is a last frost after March 15 so just be sure to be ready to protect your columbine if you have a surprise late frost.

USDA Zone Info for Silverton

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Silverton

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