The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Newberg can be looked at to estimate when you can plant spearmint.

Planting Calendar for Spearmint

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

Spearmint are one of those plants that can tolerate quite a bit of cold weather which tells us that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant spearmint in Newberg 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 spearmint and expect a good harvest is probably September. You probably don't want to wait any later than that or else your spearmint may not have a chance to grow to maturity. If you are starting your spearmint indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Newberg. You should expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Newberg is an average the actual date of last frost is different every year. Half of the time in Newberg it frosts late in the year after March 15 so always be ready to protect your spearmint in the event of one of those late frosts.

USDA Zone Info for Newberg

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 Newberg

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