One of the best tools that you have as gardeners to help us determine 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.

The USDA zone info for Keizer should be looked at 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.

Since rosemary are one of those plants that can tolerate quite a bit of cold weather you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant rosemary in Keizer 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Keizer. In the coldest months of winter you can expect an average low temperature of 15°F.

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

USDA Zone Info for Keizer

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 Keizer

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