Backyard Chicken Feed and Nutrition by Life Stage

Last updated: June 4, 2026

Getting chicken feed nutrition right is the foundation of a healthy, productive flock, and it is also where well-meaning keepers most often go astray, usually by over-treating or feeding the wrong formulation for the bird’s age. Chickens have different nutritional needs at each life stage, and matching the feed to the stage prevents problems ranging from poor growth to soft-shelled eggs to kidney strain. This guide walks through the starter-to-grower-to-layer progression, the role of calcium and grit, the all-important treat rule, and questions like scratch grains and fermented feed.

Throughout, remember that a complete commercial feed is formulated to be exactly that: complete. The single most common mistake is diluting a good feed with too many treats. We will return to that rule, but keep it in mind as the thread running through everything below.

Why Chicken Feed Nutrition Changes With Age

A chick that is rapidly building muscle and feathers needs very different nutrition from a laying hen pouring calcium into eggshells every day. Feed too much calcium to a young growing bird and you risk kidney and skeletal damage; feed too little to a layer and she pulls calcium from her own bones and lays thin, fragile shells. Matching feed to life stage is not marketing; it reflects real physiological needs that change as the bird matures. Treating the diet as a single static thing is one of the most common avoidable health mistakes in backyard flocks.

The good news is that the commercial feed industry has done the hard work for you. Properly formulated feeds for each stage exist precisely because chicken feed nutrition is a moving target, and a complete feed matched to the bird’s age delivers balanced protein, energy, vitamins, and minerals without guesswork. Your main job is choosing the right formulation for each stage and resisting the temptation to over-supplement with treats. Get those two things right and you have covered the large majority of chicken feed nutrition for a backyard flock.

Chick Starter: The First Six to Eight Weeks

From hatch through roughly the first six to eight weeks, chicks eat starter feed, formulated with higher protein (commonly around 18 to 20 percent) to fuel rapid growth, and with low calcium appropriate for young bodies. Starter is sold medicated, containing a coccidiostat to help prevent coccidiosis, or unmedicated; the right choice depends on whether your chicks were vaccinated and on your conditions, so ask your extension office or a poultry-knowledgeable vet if unsure.

Chicks should have starter available free-choice along with constant clean water. Avoid offering treats during this stage; the complete starter is doing precise work and extras dilute it. The full brooder-stage routine is covered in our guide to raising baby chicks week by week.

Grower Feed: The Adolescent Stage

After the starter phase and before laying begins, many keepers move pullets onto a grower (or a combined starter-grower) feed. Grower typically has slightly lower protein than starter and still keeps calcium low, which is exactly right for birds that are filling out their frames but not yet laying eggs.

This adolescent window matters because it is where premature calcium does the most harm. Pullets are not laying yet, so they do not need the high calcium in layer feed, and giving it to them early can damage developing kidneys. Keep growing birds on a low-calcium grower until they are at or very near point of lay, usually somewhere around 16 to 20 weeks depending on breed.

Layer Feed, Calcium, and Oyster Shell

Once hens begin laying, around 18 to 22 weeks for most breeds, switch to a layer feed. Layer feed is typically around 16 percent protein and, critically, contains added calcium (often via calcium carbonate) to support continuous eggshell production. Switching at the right time, when the first eggs appear or birds are clearly at point of lay, protects both shell quality and the hen’s skeleton.

Even with a good layer feed, offer supplemental calcium free-choice in a separate dish, usually crushed oyster shell. Hens self-regulate their calcium intake remarkably well, taking more when they need it for shells and less when they do not. This free-choice approach also lets you keep any non-laying birds in a mixed-age flock from over-consuming calcium. Thin, soft, or rough shells are a classic sign of calcium imbalance and a cue to check both feed and oyster shell access. The link between nutrition and output runs deep, as our guide to the chicken egg-laying cycle and production factors explains.

Grit: How Chickens Digest

Chickens have no teeth; they grind food in a muscular organ called the gizzard, and to do that they need grit, small hard stones held in the gizzard. Birds with constant access to coarse soil and gravel while foraging usually find their own grit, but confined birds, or any flock eating anything beyond complete pelleted feed, should have insoluble grit available free-choice.

Do not confuse grit with calcium. Grit is insoluble stone for grinding; oyster shell is soluble calcium for shells, and they serve completely different purposes. Offer both in separate dishes. Any time you feed whole grains, greens, kitchen scraps, or scratch, grit becomes essential so the gizzard can process it; without it, you risk digestive impactions. Crop and digestive troubles can follow when birds eat fibrous material without adequate grit, a topic our guide to sour crop and impacted crop addresses.

Treats, Scratch, and the 10 Percent Rule

Treats are where good intentions undo good nutrition. The widely used guideline is that treats and extras should make up no more than about 10 percent of the total diet, with the complete feed providing the other 90 percent or more. Exceed that, and you dilute the balanced nutrition, often causing reduced laying, weight problems, and shell issues.

Scratch grains deserve special mention because they are so often misused. Scratch (cracked corn and assorted grains) is a treat, not a feed; it is essentially a snack, low in the protein and balanced nutrients hens need, and it should never replace complete feed. It is useful in small amounts, especially as a cold-weather evening treat that generates digestive heat, but feeding scratch as a staple is a recipe for poorly nourished birds. Healthy treats in moderation include leafy greens and many vegetables; always pair treats with grit and keep them within that 10 percent ceiling.

Fermented Feed, Water, and Food Safety

Some keepers ferment their flock’s feed by soaking it in water for a few days until it develops a mild sour, probiotic character. Proponents report better feed efficiency and gut health, and many flocks enjoy it; if you try it, ferment only in clean conditions, feed it fresh, and discard any batch that smells foul or shows mold. Clean, fresh water at all times is even more important than any feed strategy, since hens drink heavily and a laying flock dehydrates fast.

A note on food safety and medication: backyard chickens are considered food-producing animals by the FDA even when kept purely as pets, which changes the rules around any medication. Many drugs require an egg or meat withdrawal period before products are safe to consume, and extra-label drug use legally requires a veterinarian relationship. This guide does not cover dosing; for any medicated feed or treatment questions, work with a poultry-knowledgeable veterinarian and consult our guide to when a backyard chicken needs a vet.

Common Feeding Mistakes to Avoid

Most backyard feeding problems trace back to a handful of recurring errors, and knowing them in advance saves a lot of trouble:

• Over-treating. By far the most common mistake. Kitchen scraps, scratch, and snacks feel like kindness but dilute balanced nutrition when they exceed about 10 percent of the diet, leading to reduced laying and weight problems.
• Feeding layer feed to young or non-laying birds. The added calcium in layer feed can harm growing pullets and any birds not actively laying. Use an all-flock or grower feed for mixed-age flocks and offer calcium separately.
• Skipping grit. Birds eating anything beyond complete pellets need insoluble grit to grind it, or they risk digestive impaction.
• Letting feed spoil. Damp or moldy feed can cause serious illness; store feed dry, sealed, and rodent-proof, and discard anything musty.
• Feeding bread, salty, sugary, or moldy foods. These offer little nutrition and can harm birds; stick to the complete feed plus modest healthy treats.

A mixed-age flock raises a particular question, because you may have laying hens, growing pullets, and even a rooster all eating together. The simplest solution many keepers use is to feed an all-flock or “flock raiser” maintenance feed to everyone and provide oyster shell free-choice on the side, so the layers take the calcium they need and the others take only what they need. This sidesteps the risk of feeding high-calcium layer feed to birds that should not have it. When egg quality or health concerns arise that feeding alone does not resolve, our guide to when a backyard chicken needs a vet helps you decide when to seek professional help.

Frequently Asked Questions

When should I switch chickens to layer feed?

Switch to layer feed when hens begin laying or are clearly at point of lay, typically around 18 to 22 weeks depending on breed. Layer feed adds the calcium needed for eggshells. Switching too early, while birds are still growing, exposes them to excess calcium that can harm developing kidneys, so keep pullets on grower until then.

What is the difference between grit and oyster shell?

They are completely different. Grit is small insoluble stone that sits in the gizzard to grind food, since chickens have no teeth. Oyster shell is soluble calcium that hens use to build eggshells. Offer both free-choice in separate dishes; one aids digestion, the other supports laying.

How many treats can I give my chickens?

Keep treats to no more than about 10 percent of the total diet, with complete feed making up the rest. Over-treating dilutes balanced nutrition and causes reduced laying, weight issues, and shell problems. Always provide grit when feeding anything beyond complete pelleted feed.

Is scratch grain a complete chicken feed?

No. Scratch is a treat, not a feed. It is essentially a grain snack, low in protein and balanced nutrients, and should never replace complete feed. Small amounts are fine, especially as a cold-weather evening treat, but feeding scratch as a staple leaves hens poorly nourished.

Is fermented feed good for chickens?

Many keepers report benefits in feed efficiency and gut health, and most flocks enjoy fermented feed. If you try it, ferment only in clean conditions, feed it fresh daily, and discard any batch that smells foul or shows mold. Always keep clean, fresh water available regardless of feeding method.

Chicken Food Safety Guides

Not sure which foods are safe for your backyard chicken? These guides break down common foods one at a time, with clear serving and safety advice:

• Can Chickens Eat Apples?
• Can Chickens Eat Asparagus?
• Can Chickens Eat Avocado?
• Can Chickens Eat Bananas?
• Can Chickens Eat Blackberries?
• Can Chickens Eat Blueberries?
• Can Chickens Eat Bread?
• Can Chickens Eat Broccoli?
• Can Chickens Eat Brussels Sprouts?
• Can Chickens Eat Cabbage?
• Can Chickens Eat Cantaloupe?
• Can Chickens Eat Carrots?
• Can Chickens Eat Cauliflower?
• Can Chickens Eat Celery?
• Can Chickens Eat Cheese?
• Can Chickens Eat Cherries?
• Can Chickens Eat Chocolate?
• Can Chickens Eat Corn?
• Can Chickens Eat Cucumber?
• Can Chickens Eat Eggs?
• Can Chickens Eat Garlic?
• Can Chickens Eat Grapes?
• Can Chickens Eat Green Beans?
• Can Chickens Eat Kale?
• Can Chickens Eat Lettuce?
• Can Chickens Eat Mango?
• Can Chickens Eat Mealworms?
• Can Chickens Eat Oats?
• Can Chickens Eat Onions?
• Can Chickens Eat Oranges?
• Can Chickens Eat Peaches?
• Can Chickens Eat Pears?
• Can Chickens Eat Peas?
• Can Chickens Eat Pineapple?
• Can Chickens Eat Popcorn?
• Can Chickens Eat Potatoes?
• Can Chickens Eat Pumpkin?
• Can Chickens Eat Pumpkin Seeds?
• Can Chickens Eat Raisins?
• Can Chickens Eat Raspberries?
• Can Chickens Eat Rice?
• Can Chickens Eat Spinach?
• Can Chickens Eat Squash?
• Can Chickens Eat Strawberries?
• Can Chickens Eat Sunflower Seeds?
• Can Chickens Eat Sweet Potato?
• Can Chickens Eat Tomatoes?
• Can Chickens Eat Watermelon?
• Can Chickens Eat Yogurt?
• Can Chickens Eat Zucchini?