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.

The best time to plant rosemary in Broomfield can be figured out by looking at the USDA zone info.

Planting Calendar for Rosemary

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

Rosemary tend to make it in pretty solid cold which tells us that you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant rosemary in Broomfield 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. If you wait any later than that and your rosemary may not have a chance to fully mature. Starting your rosemary indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Broomfield the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Broomfield is not always accurate the actual date of last frost will vary from year to year. Half of the time in Broomfield it frosts late in the year after April 15 so be sure to be ready to protect your rosemary if you have a surprise late frost.

USDA Zone Info for Broomfield

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Broomfield

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