What Do Chickens Eat? A Beginner Feeding Guide

The foundation: a complete formulated feed

A complete feed is exactly what it sounds like, a milled ration that carries all the protein, energy, vitamins, and minerals a chicken needs in one bag, so a bird eating it freely doesn't need anything else to be healthy. This is the part beginners underrate. It should be roughly ninety percent of the diet, available all day, and matched to the age of the flock rather than picked once and forgotten.

The feed changes as the birds grow. Chicks eat a starter crumble at about twenty percent protein from hatch to around six weeks. From there they move to a grower or pullet feed, a little lower in protein and, importantly, low in calcium, because too much calcium before laying is hard on the kidneys of a young bird. Once a hen begins to lay, at roughly eighteen to twenty weeks, she switches to a layer feed at about sixteen percent protein with the added calcium she now needs to build eggshells. Keep the feed clean and dry and let the birds eat it whenever they want.

Grit and oyster shell aren't the same thing

These two get confused constantly, and they do completely different jobs. Grit is insoluble, small hard stones a chicken swallows so its gizzard can grind food, because a hen has no teeth. Oyster shell is soluble calcium that a laying hen uses to build strong eggshells. One is for digestion, one is for the shell. A flock often needs both, offered separately, and neither is a substitute for the other.

Grit matters most when birds eat anything other than plain feed. A chicken that free-ranges picks up small stones on its own and usually needs no help, but a confined flock eating scratch, greens, or scraps has nothing to grind with, so you set out insoluble poultry grit free-choice and the birds take what they need. Oyster shell works the same way but only for layers: put it in a separate small hopper alongside the feed, offered free-choice, and each hen eats to her own calcium demand. Don't mix calcium heavily into feed meant for chicks or roosters, who don't need the load.

Treats and scraps: keep them under ten percent

This is the rule that saves beginners the most trouble. Treats are fine and the birds love them, but they should stay under about ten percent of the daily diet, because everything you hand out beyond the feed dilutes the careful balance in that feed. Fill a hen up on cracked corn and she eats less layer feed, gets less calcium and protein, and lays worse. The treat ceiling isn't a killjoy rule, it's what keeps the complete feed doing its job.

Good treats in that ten percent include scratch grains (a scattered mix of cracked corn and grains, best used as a small afternoon handful), leafy greens and vegetable trimmings, and dried mealworms or other insects for a protein boost, which hens go wild for. Garden vegetables, most fruit, and plain kitchen scraps are fine in moderation. The trick is to treat all of it as a garnish, a scattered handful for the flock rather than a meal, so the feed stays the thing they fill up on.

Foods to keep away from the flock

A few foods are worth keeping out of the run as a matter of feeding safety, the same way you wouldn't leave them where a curious pet could get a bellyful. This is a shopping-list rule, not a health warning: just don't offer these to chickens. Avocado, both the flesh and the pit, contains a compound birds don't handle well. Raw or dried beans should never be fed, though fully cooked beans are fine. Moldy or spoiled food goes in the bin, not the run. Chocolate and anything with a lot of caffeine are off the list, as is very salty food in any quantity.

A couple more to skip: large amounts of raw onion, and rhubarb leaves. None of this makes chicken-keeping fussy, because the safe list is enormous and the avoid list is short. When you're unsure about a scrap, the simple move is to leave it out rather than test it on the flock, and to keep the complete feed as the thing the birds actually rely on. Fresh, unspoiled, and offered in moderation is the whole standard for treats.

Foraging and free-ranging

Chickens are natural foragers, and a flock with room to roam does a lot of its own feeding: bugs, worms, grubs, grass, weeds, and seeds all go down happily and add protein and variety that a bag can't. This is real food, not just enrichment, and in the warm months a free-ranging flock noticeably lowers the feed bill because the birds simply eat less from the feeder when the yard is full of insects and greens.

The catch is that foraging is seasonal and uneven. A summer lawn feeds a flock well, but a bare winter yard or a small run offers little, so the complete feed is always the backstop that fills the gap. Treat forage as a welcome supplement that shrinks the feed bill in season, not as a diet you can count on year-round, and keep the feeder full regardless so the birds never go short when the bugs run out.

Water, the other essential

Feed gets all the attention, but water is the input a flock can't go without, and a hen drinks far more than beginners expect, especially in heat and while laying. Water should be clean and available all day, every day. Chickens foul it fast with bedding and droppings, so the practical job is keeping it clean, which is why enclosed or nipple-style waterers beat an open dish, and why the supply needs checking daily and topping in hot weather. A hen short on water stops laying quickly, so this isn't the corner to cut.

If you want to see what feeding a flock actually costs before you commit, our feed cost calculator estimates the monthly bag spend by flock size, and once you know that, our guides to the right feeder in our best chicken feeder buying guide and to keeping the bag safe in our rundown of the best rodent-proof feed storage cover the two pieces of gear that decide whether that feed reaches the hens or the rats.