What to Feed Chickens (and What Not To)

Feeding hens well is far simpler than most beginners expect. A good-quality complete layers feed, plus grit and a constant supply of fresh water, covers around 90% of what your birds need to stay healthy and lay well. Everything else — the treats, the greens, the kitchen-garden offcuts — is the small remaining slice, and there are a few firm rules about what must never go in the run. Get the basics right and the rest falls into place.

This guide sits alongside our beginner chicken guide, which covers the whole picture of getting started. Here we focus purely on the food bowl.

Start with a complete layers feed

A "complete" feed is exactly what it sounds like: it contains everything a laying hen needs — protein, calcium, vitamins and minerals — in the right balance, so you don't have to mix anything yourself. For hens that are laying, you want a layers feed, which is higher in calcium to support eggshell formation. This is the foundation of the diet, and it should be available to your birds all day.

You'll find it sold two ways:

• Layers pellets — small, uniform pellets. Most keepers prefer these because the birds can't pick and choose, so they eat the balanced ration rather than just the bits they fancy. There's also less waste.
• Layers mash — a coarse, floury blend of the same ingredients. Some hens enjoy mash and it can be served dry or dampened into a porridge. The downside is that it's easier to scatter and waste, and birds can selectively eat the tastier fractions.

Either is fine nutritionally. If you're unsure, start with pellets — they're tidier and more foolproof for a first flock.

When to switch from growers to layers

Younger birds need different feed. Chicks start on chick crumb, move on to growers pellets or mash as they mature, and only switch to layers feed when they reach point of lay — typically around 16 to 20 weeks, when they're about to start producing eggs. Switching to high-calcium layers feed too early, before the birds are laying, can strain young kidneys, so don't rush it. If you've bought hens at point of lay (the usual route for beginners), they'll already be ready for layers feed.

Grit and oyster shell

Chickens have no teeth. To break down their food they swallow small, hard particles that sit in the gizzard — a muscular part of the gut — and grind everything up. That's what grit is for. Hens that free-range over soil often pick up enough naturally, but it's good practice to offer a dish of insoluble flint grit so it's always available, especially for birds kept on a hard standing or in a run with little bare earth.

Separately, laying hens need plenty of calcium to build strong eggshells. Although a complete layers feed already contains calcium, many keepers also put out a small bowl of crushed oyster shell (sometimes sold as "soluble grit"). The hens take what they need. Thin, soft or shell-less eggs are often a sign a bird is short of calcium, so oyster shell is cheap insurance.

The two aren't interchangeable: flint grit is for grinding and isn't digested; oyster shell dissolves and is absorbed as calcium. Offering both, in separate dishes the birds can help themselves to, keeps everyone covered.

Fresh water, always

Water matters as much as feed — arguably more. A laying hen drinks far more than people expect, and even a few hours without water can knock egg production and, in hot weather, become dangerous quickly. Eggs are mostly water, so a hen that can't drink can't lay.

Provide clean, fresh water at all times and change it daily. A few practical points for UK conditions:

• Keep it clean. Hens are good at fouling open dishes with bedding and droppings. A purpose-made drinker keeps the water cleaner than a bowl.
• Site it in shade where you can, so it stays cool in summer.
• Watch for ice in winter. UK frosts will freeze a drinker solid overnight. Check it first thing on cold mornings and break or refresh the ice; some keepers keep a spare drinker indoors to swap in.

Safe treats, in moderation

Treats are where keeping hens gets fun — they'll come running for a handful of corn — but they're genuinely a treat, not a meal. The rule of thumb is the 10% rule: treats and extras should make up no more than about 10% of what your birds eat in a day. The other 90% is the complete feed that keeps them properly nourished. Overdo the treats and you'll see softer eggs, fatter birds and, often, fewer eggs.

Good, safe things to offer:

• Mixed corn / whole wheat — a classic scratch feed. Hens love it, and scattering a little in the afternoon encourages natural foraging. It's a treat, though, not a substitute for layers feed, as it's low in protein and calcium.
• Leafy greens and brassicas — cabbage, kale, lettuce, spinach, chard and the like. Hanging a cabbage on a string keeps them busy on a wet day.
• Garden veg and trimmings — courgette gluts, pea pods, sweetcorn, and the outer leaves and tops you'd otherwise compost.

This is where chickens and your veg patch work beautifully together — many of the offcuts, bolted greens and surplus crops from the plot are exactly what hens enjoy. Our guide to keeping chickens and your vegetable garden covers how to feed them garden produce safely and use the birds to clear and fertilise beds. If you grow your own, a courgette glut or a tray of bolted lettuce is a welcome treat. Crucially, this garden produce is fed straight from the plot — not via the kitchen, which is where the law comes in.

What NOT to feed — and the UK law

This is the part every UK keeper must get right. Under DEFRA rules it is illegal to feed kitchen or catering waste to poultry — including hens kept purely as pets in your own back garden. This means anything that has passed through a kitchen, even a domestic one, is off-limits: peelings, plate scrapings, leftover cooked food, bread, and so on. The ban exists to reduce the risk of serious livestock diseases such as avian influenza and African swine fever, which can spread through contaminated food. It applies regardless of whether the kitchen is vegetarian.

The safe way to think about it: garden-grown greens and veg fed direct from the plot are fine; anything from the kitchen is not. A cabbage cut from the garden and handed to the hens is legal; the same cabbage once it's been in your kitchen is not.

Beyond the law, a few foods are simply bad for hens and should always be avoided:

• Mouldy or spoiled food — mould toxins can be dangerous; never feed anything going off.
• Raw or green potato and potato peelings — these contain solanine, which is toxic to chickens.
• Avocado — the skin and stone contain persin, which is harmful to birds.
• Anything very salty, sugary or heavily processed.
• Raw dried beans — uncooked, they contain compounds that are toxic.

How much, and when

Hens are good at self-regulating, so the simplest and most reliable approach is to feed your complete layers ration ad lib — that is, always available — in a feeder the birds can help themselves to through the day. They'll eat what they need and stop. As a rough guide, an average laying hen gets through somewhere around 120–150g of feed a day, but you don't need to weigh it; keep the feeder topped up and let them manage.

A sensible daily routine looks like this:

1. Morning: check and refill the water, top up the feeder, let the birds out.
2. Through the day: complete feed available at all times; grit and oyster shell in their dishes.
3. Late afternoon: a small scatter of corn or some greens as a treat (within the 10% rule).
4. Evening: quick check that water's clean and the feeder isn't empty before they roost.

Keep feed dry and in a vermin-proof container — an open sack in a shed is an invitation to rats and mice. A galvanised bin with a tight lid does the job. Lifting the feeder off the ground overnight, or using a treadle feeder, also helps keep rodents out.

What you'll need

Once you understand why each item matters — complete feed for nutrition, grit for digestion, a clean drinker for constant water — the kit itself is straightforward and inexpensive. These are the few basics that cover feeding a small back-garden flock.

Where to go next

Feeding is one piece of a happy flock. For everything else — choosing breeds, housing, daily care and the legal basics — head back to our beginner chicken guide. If you grow your own food too, see how hens and the plot work together in chickens and your vegetable garden, and browse the full keeping chickens section for more.