Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when it's a good idea to plant dahlia in Honolulu by looking at the USDA zone info.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's a bad idea to plant dahlia until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant dahlia 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 dahlia and expect a good harvest is probably November. If you wait any later than that and your dahlia may not have a chance to really do well. If you are starting your dahlia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Honolulu is an average and the actual date of last frost is different every year. Since it never frosts in Honolulu you do not have to be ready to cover your dahlia if you have a late frost.

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.