One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Manhattan you can determine when it's a good idea to plant alyssum by reviewing the USDA zone info.

Planting Calendar for Alyssum

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

Alyssum do well in a bit of cold which tells us that you can plant them quite a bit earlier in the year than other frost tender plants.

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

Last Frost Date

On average the last frost is on April 15 in Manhattan. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Manhattan is just an average 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 be sure to be ready to protect your alyssum if you have a surprise late frost.

USDA Zone Info for Manhattan

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Manhattan

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