The standard farm-store chicken feed shelf has eight to twelve labeled products, and many new keepers buy whatever bag is at eye level. The result is chicks fed layer pellets at three weeks (calcium toxicity), pullets fed starter at sixteen weeks (protein burn and missed laying onset), and mixed flocks fed straight layer (rooster kidney damage and unnecessarily stressed cockerels). Feed type and timing is one of the highest-leverage decisions in a chicken flock, and it is genuinely simple once the three main rations are understood. This guide explains starter, grower, layer, and the niche feeds, what each is formulated for, when to switch, and the most common mistakes.
The three core feeds
Commercial chicken feed splits into three life-stage products:
- Starter: 20 to 22 percent protein, low calcium. Day 1 to week 6 to 8.
- Grower: 16 to 18 percent protein, low calcium. Week 6 to 8 until laying.
- Layer: 16 to 18 percent protein, 3.5 to 4.5 percent calcium. From first egg onward.
Each is built around two main variables: protein for growth, calcium for shell formation. Get the protein-calcium pairing right for the life stage and the bird does the rest.
Starter feed: weeks 0 to 8
Starter is the high-protein, low-calcium ration that supports rapid early growth. Chicks gain 10 to 15 times their hatch weight in the first eight weeks. The protein level is the single most important variable in that window.
Standard chick starter: 20 percent protein.
Game bird / broiler starter: 22 to 24 percent protein, used for fast-growing meat birds.
Medicated vs unmedicated: Medicated starter contains amprolium at roughly 0.0125 percent. It is a coccidiostat, not an antibiotic. Use medicated if your chicks were not vaccinated against coccidiosis and you are raising in conditions with any disease pressure (used litter, mixed-age flocks, outdoor brooder). Use unmedicated if your chicks were vaccinated, because amprolium blocks the vaccine response.
Form: Almost always crumble. Pellets are too large for week-1 chicks. Most starter feed remains crumble through week 8.
Water: Chick starter requires constant clean water. A chick can die from 12 hours without water. Quart waterers for the first two weeks, gallon waterers thereafter.
Grower feed: weeks 8 to first egg
Grower is the moderate-protein, low-calcium maintenance feed for pullets through the pre-laying window. It is the longest-running feed in a layer flock’s life, covering weeks 8 through 16 to 24 depending on breed.
Standard grower: 16 to 18 percent protein.
Why drop the protein: A 20 percent protein feed past week 8 wastes protein (excreted, not used) and can over-condition pullets, which delays laying and increases the risk of fat-deposit problems in adulthood. The 16 to 18 percent protein matches the slowing growth rate.
Calcium stays low. Calcium in grower runs 0.9 to 1.1 percent. The pullet’s reproductive tract is developing, but the shell gland is not active yet. High calcium during this period causes kidney damage and gout.
Skip-the-grower approach: Some keepers use a 16 percent protein “all-flock” or “flock-raiser” feed from week 8 onward. This works fine and simplifies feed storage at the cost of slightly less optimal protein for fast-growing breeds.
Layer feed: first egg onward
Layer is the moderate-protein, high-calcium ration that supports daily egg production. The calcium jump from 1 percent (grower) to 4 percent (layer) is the most important transition in the feed table.
Standard layer: 16 to 18 percent protein, 3.5 to 4.5 percent calcium.
High-protein layer: 18 to 20 percent protein for heavy-laying breeds or molting hens. Useful as a temporary boost, not a permanent ration.
Timing of the switch: When the first egg appears, not at a fixed week. Pullets start laying anywhere from week 16 (Leghorns, ISA Browns) to week 28 (Buff Orpingtons, Wyandottes in winter). Switching to layer feed before laying starts forces calcium through a non-laying kidney and causes long-term damage.
Form: Pellet or crumble, both work. Pellets reduce waste because birds cannot scratch them out of the feeder as easily. Crumble is easier for bantams and smaller breeds.
All-flock and flock-raiser feeds
Mixed-age flocks (pullets, layers, roosters together) need a single feed that is safe for all of them. Straight layer feed harms roosters and growing birds over time, so the solution is an “all-flock” or “flock-raiser” feed.
All-flock specification: 16 to 18 percent protein, 1 to 1.5 percent calcium.
Oyster shell offered separately: Laying hens get the calcium they need from a separate dish of crushed oyster shell, which non-laying birds ignore by instinct. This is the most flexible feeding system for a mixed flock and the one I default to.
When to use all-flock:
- Mixed-age flock (any non-laying birds present)
- Roosters in the flock
- Flock during molt (non-laying period)
- Flocks where some hens have stopped laying due to age
Specialty feeds
Broiler grower: 18 to 22 percent protein, used for Cornish Cross from week 3 through processing. Cornish Cross need higher protein for their growth rate.
Game bird feed: 24 to 28 percent protein, used for pheasants, quail, turkeys, and some peacocks. Not appropriate for chickens past week 4.
Scratch grains: Not a feed, a treat. Scratch is 8 to 10 percent protein, no balanced nutrition. Use as a small daily treat (less than 10 percent of total intake) or in winter for warmth (the bird burns calories digesting it overnight).
Fermented feed: Standard feed soaked in water for 2 to 4 days. Improves digestibility and feed conversion by 5 to 15 percent. Adds management overhead.
Common feeding mistakes
Feeding layer feed to chicks or roosters. Calcium toxicity in non-laying birds is the single most common feed mistake. It is silent, cumulative, and produces kidney damage by month 6.
Feeding starter past week 12. Wastes protein, over-conditions birds, increases fat deposition.
Feeding scratch as a meal. Scratch is candy, not food. A bird that fills up on scratch is malnourished even if the bowl is full.
Switching feeds abruptly. Transition over 5 to 7 days by mixing increasing ratios of new feed into old. Sudden switches cause crop and gut disruption.
Feeding stale or moldy feed. Aflatoxin from moldy feed is one of the most serious silent killers in a backyard flock. Buy feed in monthly quantities and store dry and rodent-proof.
Daily feed budget
A standard-size laying hen eats about 0.25 pounds (113 grams) of feed per day. A six-hen flock consumes:
- Daily: 1.5 pounds
- Weekly: 10 to 11 pounds
- Monthly: 45 pounds
- Annual: 500 to 550 pounds
Free-range access reduces feed intake by 10 to 25 percent depending on forage quality. A flock on summer pasture with good insect availability can drop to 0.18 to 0.20 pounds per bird per day. A flock locked in a bare run keeps intake at the full 0.25 pounds per bird per day.
See our methodology for the framework behind our poultry husbandry guides.
Frequently asked questions
When should I switch chicks from starter to grower feed?+
Between weeks 6 and 8 for most breeds. Starter feed runs 20 to 22 percent protein, grower drops to 16 to 18 percent. Switching too early under-feeds the rapid growth phase, switching too late wastes money. Cornish Cross broilers may stay on a higher-protein broiler ration until processing rather than moving to grower.
When does layer feed start?+
At first egg, not at a fixed age. Most pullets start laying between 16 and 24 weeks depending on breed, season, and daylight. Layer feed has 3.5 to 4.5 percent calcium for shell formation, which is toxic to non-laying birds because the kidneys cannot process it. Switch when you find the first egg, not on a calendar.
Can I feed all my chickens the same feed?+
Only if all birds are in the same life stage. A mixed flock with pullets, layers, and a rooster needs an all-flock or flock-raiser feed (16 percent protein, 1 percent calcium) with oyster shell offered separately for the laying hens. Layer feed harms roosters and growing pullets over time.
Is medicated chick starter necessary?+
Only in high-risk situations. Medicated starter contains amprolium, a coccidiostat that prevents coccidiosis. Use it if you raise chicks on used litter, in a high-stocking density brooder, or with a known coccidia history on the property. Vaccinated chicks should not get medicated feed, the medication interferes with the vaccine.
How much feed does a laying hen eat per day?+
Quarter pound (113 grams) per day for a standard-size laying hen, slightly less for Leghorns and bantams, more for heavy breeds like Brahmas. A six-hen flock goes through roughly 10 pounds of feed per week, or 500 to 550 pounds per year. Free-range access reduces feed intake by 10 to 25 percent depending on forage quality.
Priya Sharma
Priya Sharma writes for The Tested Hub.