Quote!I pruned back my kale in July-August, as the leaves were turning dark yellow and brown.

What sort of temperatures has it been growing in?

Kale is grown as a cool weather plant here in the UK where our temperatures tend to range between Zone 7 to 9

I am guessing yours have been growing in one of the lower zones.

Quote; Was I wrong to prune it? Will it come back now that the weather's cooled?!

Not really as it was ruined by then, and no it won't come back!

OK you might get a few leaves growing at the top of the stem but that about it I would have thought!

Next year do not start it so early.

Plan it that you are planting out at the end of summer then it will mature in autumn (Fall) and grow on into the winter.

BTW this is only an opinon as I have no experience of growing in your part of the world!

I would be interested to know what conditions you did grow it under, then perhaps I could add to my comments after I know this.

Sorry I couldn't be of more help to you!....Tg

I don't know too much about your weather in New Jersey but I would be surprised if it easily gets through the winter if it is extremely cold as even here in France it is set back.
If I am wrong and you can overwinter kales with a little protection, then as said above you should sow much later say July, so that the plant will have made plenty of growth by autumn but be hardy enough to survive.
Even here in northern France we often have trouble keeping certain kales going as the oscillation between very cold and mild weather in winter tends to turn them to mush, even the stems.

Thanks Bertie and Teegee,

To answer your inquiries, I'm in New Jersey, USA, and the kale was growing in temps. in 80s-90s, and getting unruly, plus going to seed. It DID overwinter from last year, but we had a warm (20s-40s) winter. Honestly, both plants were 3-4 feet tall and 2-3 feet wide when I pruned them!
Maybe I'll have to see what develops next spring! We had kale on sandwiches during December ... came in quite handy if there was no lettuce from the grocery store in our fridge!