Before planting it is a good idea to find your USDA Zone info to figure out 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 should be able to determine when it's a good idea to plant flowering kale by using the USDA zone info for Alton.

Planting Calendar for Flowering Kale

Frost tolerance for flowering kale:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Flowering Kale do well in moderate cold which means that you can plant them a little bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant flowering kale in Alton 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 flowering kale and expect a good harvest is probably September. You probably don't want to wait any later than that or else your flowering kale may not have a chance to fully mature. If you are starting your flowering kale indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Alton the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Alton may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Alton there is a last frost after April 15 be ready to protect your flowering kale if you have a surprise late frost.

USDA Zone Info for Alton

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 Alton

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