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.

You should be able to figure out when it's the best time to plant sunflowers by checking out the USDA zone info for Honolulu.

Planting Calendar for Sunflowers

Frost tolerance for sunflowers:	Not tolerant of frost.
When to plant:	After the last frost.

You really shouldn't plant sunflowers until after the last frost has passed because they require warm weather.

The earliest that you can plant sunflowers 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 sunflowers and expect a good harvest is probably November. If you wait any later than that and your sunflowers may not have a chance to really do well. You can get started a couple of weeks earlier by starting your sunflowers indoors.

Last Frost Date

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

Always keep in mind that USDA zone info for Honolulu is just an average and 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 protect your sunflowers 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.