When to Plant Flowering Kale in Grinnell, IA

One of the first steps you take when you are determining your gardening schedule is find your 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.

It's a good idea to figure out when it's the best time to plant flowering kale by checking out the USDA zone info for Grinnell.


Planting Calendar for Flowering Kale

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

Since flowering kale are moderately cold tolerant you can plant them a bit earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant flowering kale
Possibly ok, but a risky time to plant flowering kale
Probably not a good time to plant flowering kale

The earliest that you can plant flowering kale in Grinnell 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. If you wait any later than that and your flowering kale may not have a chance to fully mature. Starting your flowering kale indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Grinnell. In the coldest months of winter you can expect an average low temperature of -20°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Grinnell and it can change quite a bit from year to year. Half of the time in Grinnell it frosts late in the year after April 15 so make sure that you are prepared to cover your flowering kale in the event of one of those late frosts.

USDA Zone Info for Grinnell

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Grinnell

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