Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Manhattan it's a good idea to estimate when it's the best time to plant hardy hibiscus.

Planting Calendar for Hardy Hibiscus

Frost tolerance for hardy hibiscus:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

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

The earliest that you can plant hardy hibiscus in Manhattan is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant hardy hibiscus and expect a good harvest is probably September. Any later than that and your hardy hibiscus may not have a chance to fully mature. Starting your hardy hibiscus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Manhattan the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Manhattan may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Manhattan you get a frost after April 15 so always be ready to cover your hardy hibiscus in the event of one of those late frosts.

USDA Zone Info for Manhattan

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Manhattan

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