I only grain when it needs help gaining weight or is consistently working. It really depends on how they maintain weight. My QH maintained without grain getting ridden 3-4 times a week for 1-2 hours. He had free access to hay. If you don't ride but once a week, don't worry about graining. They didnt have commercialized grain 100 years ago, people forget this :) (or dog/cat food for that matter!!)
Best thing to do is keep your eye on the horse's weight, and if you are unsure buy a $2 weight tape and have at it. This is the best way to tell if you are doing things correctly - weight and muscle tone (which has much to do with riding). Regular access to quality hay is the best diet for a horse that is a past time horse that has no serious ailments.
I use pellet and sweet grain, beet bulp, supplements, alfalfa cubes, and corn oil ONLY as tools to meet a horse's needs. If they do not require the extra calories or have an ailment, they don't get grain. This is because I feel it is pointless to mindlessly give a horse a partial scoop. I used to do it when I was in middle school, then I realized how much money I was wasteing - but not only that, they just didnt need the grain! Winter time is an exception because some horses need a little boost. But at a place with excellent hay, this is not needed often. There is a major difference between a horse fed decent/crappy hay and a horse fed nice, green lucious hay. The horse on the crappy hay won't maintain and you'll think you need grain, when really, you just need more grass and better hay.
I try to work up the latter into grain as well. If there is a weight issue, I worm everything on the farm and I do alfalfa flakes if I can get my hands on it, if not - then cubes. If that doesnt help, I douse them in corn oil. If still not enough I buy grain.
Last edited by 94broncoxlt; 04-14-2012 at 12:43 PM.