One of the best tools that you have as gardeners to help us determine 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 estimate when it's possible to plant alyssum by checking out the USDA zone info for Columbus.

Planting Calendar for Alyssum

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

Alyssum tend to make it in pretty solid cold which means that you can plant them quite a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant alyssum in Columbus 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. You probably don't want to wait any later than that or else your alyssum may not have a chance to really do well. You can get started a couple of weeks earlier by starting your alyssum indoors.

Last Frost Date

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

Just be sure to remember that USDA zone info for Columbus is an average and the actual date of last frost is different every year. Since half of the time in Columbus you get surprised by a frost after April 15 be ready to protect your alyssum in the event of a surprise late frost.

USDA Zone Info for Columbus

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 Columbus

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