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

One way of figuring out when it's the best time to plant rosemary is to check out the USDA zone info for Honolulu.

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 a bit of cold which means that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant rosemary in Honolulu is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant rosemary and expect a good harvest is probably November. If you wait any later than that and your rosemary may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your rosemary indoors.

Last Frost Date

In Honolulu it never frosts. You can expect an average low temperature of 50°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Honolulu and it will vary from year to year. Since it never frosts in Honolulu you do not have to be ready to protect your rosemary in the event of one of those late frosts.

USDA Zone Info for Honolulu

Here is the info for USDA Zone 12a.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	50°F
Highest Expected Low	55°F

This means that on a really cold year, the coldest it will get is 50°F. On most years you should be prepared to experience lows near 55°F.

Plants to Grow in Honolulu

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