I was blessed today …my local produce wholesaler is giving me their leftovers and scraps for my piggies. There is so much good stuff here, like cantaloupe and pineapple rinds, I wonder if I could give it to my horses? I could dehydrate them or grind them into a slurry if they would be beneficial to my horses. There’s so much here I don’t think my piggies and chickens can eat it all so if there is something the horses can have, please let me know. I will be getting this daily and it will vary what I will bring home so if there’s a list of of good fruits and vegetables for horses and ones I should stay away from, please let me know!
ETA: specifically wondering about rinds/ skins. I know the rinds could be a chocking hazard but is there anything in them that is toxic to horses? I can grind the rinds up into smaller pieces or blend them into a slurry and add them to their feed.
I’ve never given my horses pineapple but they absolutely love cantaloupe and watermelon rinds!
Don’t feed tomatoes, peppers (green or red peppers), eggplant, avocado, broccoli, cauliflower, onions, raw potatoes (there may be more). I’d be hesitant about lettuce.
Be careful with peaches, nectarines or cherries with stones.
I would just pick out the good stuff and not feed a “mix” in case it contains something bad for horses. I would not feed too much fruit, though.
I’ve fed bananas and watermelon as treats.
Mine devours oranges, but likes watermelon and bananas too. At one show there are raspberry bushes lining the road and he carefully takes the ripe ones off the bushes. He won’t touch one if you hand it to him though, no idea why…
When he first arrived, I thought he was using his tongue to kind of wind suck. Turns out when he eats things that produce saliva, he sucks on his tongue to get more of the flavour. He will suck on a peppermint for a bit before you hear him crunch it, then sucks on his tongue to get all the juice haha. He does that with oranges too, but no other fruit.
My daughters horse loves bananas best, then watermelon. Doesn’t care for grapes or strawberries but many of the others do.
Here are the things I’ve tried, and whether or not my horse liked them:
Yes: carrots, apples, pears, blueberries
No: banana (peeled), orange, watermelon (did not want the flesh or the rind!), strawberry, apricot, grapes (ate a few the first time I offered but not since), celery
I was surprised how soundly he rejected the watermelon! I thought that would be a hit for sure. He doesn’t like peppermints either.
Mine like Broccoli stems and the bottom of Romaine lettuce. Corn husks too. Almost as good as carrots
I had one foal who LOVED the Daikon radishes I threw over the fence. None of the other horses would eat them, but she relished them.
Let the chickens have the rinds.
I don’t know that I’d want to introduce the prickly parts of a pineapple to my horses’ guts.
Sweet potatoes are a big hit here - uncooked, cut into chunks.
Pears too - cause for some serious droolage.
And - amazing to me - plain, uncooked pasta, any shape. I keep spaghetti on hand to give kids to feed - keeps little fingers a safe distance.
I tried bananas - based on postings here - & no dice.
Zucchini & pumpkin are not accepted either - noone touched the excess that sprawled from a garden into their pasture. They did step on them creating a nice mess.
Speaking of mess:
I had a neighbor who decided my horses needed fruit salad - mixed with garlic.
All sorts of berries, lettuce, celery, etc.
And would fill their buckets with the mess.
That I had to toss & rinse daily to get the garlic stench out.
Bananas - peel and all- are a massive hit. Apples and oranges and carrots are good. Blackberries right from the bushes including leaves and thorns also a hit! How they eat the thorns is beyond me but they do.
P.
My horse loves bananas and sweet potatoes
Just adding that the first times I offered banana and watermelon my horse was highly suspicious and would not even try them. After a couple more offerings, he now relishes both and is more apt to try things I offer.
What about the rinds though? Are they toxic or safe if given in small pieces?
Not a fruit or vegetable but my horses get peanuts in their shells as treats. They love them and are a lot easier to store and handle for me. I used to have carrots on hand but in the summer they got mushy and in winter they froze.
All my coat pockets seem to contain peanuts and my horses know this. There are always a few in the feed bins when they come in. They get one at the gate when they go out which keeps them from wanting to take off right away.
My horse is obsessed with bananas and mangoes. Dried or fresh, he doesn’t care. The other one likes clementines. Not any other citrus, just clementines. He also eats sweet potatoes that are mixed in with his lunch in the winter.
The rinds are fine for them. (I wouldn’t feed pineapple rind because of the spiky surface)
With horses, goats, chickens, and barn cats, most of our kitchen scraps are fed to the animals. Our horses like pretty much all fruit except citrus. They also get leftover lettuce, veggies, bread, etc. Pumpkin and squash are big hits, too.
Everything in moderation, of course. It’s not like I’m dumping it out there in 5gal buckets.
What is wrong with raw potatoes? My old horse and pony used to love the potato peels my mom used to throw to them from her basket of supper prep stuff (before composting was cool, never saw them touch any of the other stuff), but the pony lived to be 35 and the mare was well into her late 20s last time I saw her. Didn’t seem to do any long term damage to them.
In response to the OP, my horses/ponies loved, absolutely loved cucumbers! They used to line up at the fence that separated them from the vegetable garden when my dad went through it and started throwing the over mature ones over the fence. Again, they lived long and healthy lives. 
Because of the possibility of solanine poisoning if fed raw:
http://www.horseandhound.co.uk/horse-care/vet-advice/poisonous-plants-potatoes-36108
There’s probably little risk if feeding small amounts. I think it can be avoided if you make sure there are no greenish areas on the potato skin.
Is the sugar content of whole beets too great to feed? I don’t like beet pulp and beet shreds in winter but want my horses to eat beets. Lots of sugar in fresh ones though.
Whatever you buy, remember a lot of fruits and veggies are treated with chemicals to keep them from turning brown. Not good for horses, especially from salad bars in restaurants.
