When to Plant Delphinium in Winston, OR

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.

A common way of determining when you can plant delphinium is to consult the USDA zone info for Winston.


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 start planting them slightly earlier than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant delphinium
Possibly ok, but a risky time to plant delphinium
Probably not a good time to plant delphinium

The earliest that you can plant delphinium in Winston 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. If you wait any later than that and your delphinium may not have a chance to fully mature. Starting your delphinium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Winston may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Winston you get surprised by a frost after March 15 be ready to cover your delphinium in the event of a surprise late frost.

USDA Zone Info for Winston

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 Low15°F
Highest Expected Low20°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 Winston

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