In short, if you are wondering if your dog can eat kale, the answer is yes, but in moderation. Like all other things, dogs should not eat an excess of kale. Kale is high in calcium, and can lead to kidney/bladder stones if eaten in excess for long periods of time.
More Information About Kale For Dogs
If your dog enjoys eating greens, or you would like to introduce more greens into your dogs diet, giving your dog small amounts of kale could be a good idea. Although dogs may not be drawn to eat kale when living in the wild, many dogs actually enjoy the taste. Because of the high calcium in kale, you should not feed dogs large quantities, and only on occasion.
It is important to note that the safe amount of kale is dependent on the size of your dog. While large dogs can safely eat a larger quantity of kale, small dogs should not be given much. With that said, you should not be giving your dog more than a couple leaves once a week.