When to Plant Rosemary in Mount Vernon, WA

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

By referring to the USDA zone info for Mount Vernon you will be able to determine when to plant rosemary.


Planting Calendar for Rosemary

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

You can plant rosemary a lot earlier in the year because they do well in cold.

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

The earliest that you can plant rosemary in Mount Vernon 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 rosemary and expect a good harvest is probably September. Any later than that and your rosemary may not have a chance to grow to maturity. If you are starting your rosemary indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Mount Vernon the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

Always keep in mind that USDA zone info for Mount Vernon is an average and the actual date of last frost will vary from year to year. Half of the time in Mount Vernon you get surprised by a frost after March 15 so always be ready to protect your rosemary in the event of one of those late frosts.

USDA Zone Info for Mount Vernon

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 Low10°F
Highest Expected Low15°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 Mount Vernon

You may be interested in your other planting guides for Mount Vernon.