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.

By referring to the USDA zone info for Honolulu it's a good idea to determine when you can plant calendula.

Planting Calendar for Calendula

Frost tolerance for calendula:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since calendula are moderately cold tolerant you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant calendula 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 calendula and expect a good harvest is probably November. You probably don't want to wait any later than that or else your calendula may not have a chance to grow to maturity. Starting your calendula indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Honolulu it never frosts. It might get as low as 50°F during the coldest months of winter.

Since the USDA zone info for Honolulu is just an average the actual date of last frost will vary from year to year. Since it never frosts in Honolulu you do not have to be ready to cover your calendula if you have 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.