One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when you can plant catharanthus in Honolulu by reviewing the USDA zone info.

Planting Calendar for Catharanthus

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

You really shouldn't plant catharanthus until after all chance of frost has passed because they require warm weather.

The earliest that you can plant catharanthus 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 catharanthus and expect a good harvest is probably November. If you wait any later than that and your catharanthus may not have a chance to grow to maturity. Starting your catharanthus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Honolulu is 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 cover your catharanthus 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.