Can Chickens Chow Down On Onions? The Complete Guide

Onions are a common ingredient in many kitchens, but should you share them with your backyard chickens? This complete guide covers everything you need to know about feeding onions to chickens.

Article Summary

  • Chickens can eat onions, but it should be done in moderation, as large amounts of onions can be harmful due to the presence of thiosulphate.
  • Chickens can eat both raw and cooked onions, with slight variations in their nutritional content, and they can be used as treats in controlled proportions.
  • Onions offer some health benefits for chickens, including prebiotics, antioxidants, vitamins, and minerals, which can support their gut health and immunity.

Is it safe to feed chickens onions?

Onions contain compounds that can be harmful to chickens in large quantities. Small amounts of onions are usually safe, but moderation is key.

Onions contain compounds that can be harmful to chickens in large quantities…

The primary concern with feeding onions is a compound they contain called thiosulphate. When ingested, thiosulphate can cause hemolytic anemia in chickens. This condition impairs the oxygen-carrying capacity of the blood.

Onions also contain disulfides and sulfoxides. In large amounts, these compounds can cause gastroenteritis and potentially fatal conditions like aortic rupture. Baby chicks under 6 months old seem especially sensitive to the effects of these compounds.

So can chickens eat onions safely? Yes, in moderation. The occasional slice of onion or bit of scrap won’t harm them. But onions should never make up more than 10% of a chicken’s diet.

Health Benefits of Onions for Chickens

Despite the potential risks, onions do offer some health benefits for chickens:

  • Prebiotics: Onions are a source of the prebiotics inulin and fructooligosaccharides that support healthy gut bacteria.
  • Antioxidants: Onions contain antioxidants like quercetin that reduce inflammation and boost immunity.
  • Vitamins & Minerals: Onions provide small amounts of vitamins like vitamin C, folate, and vitamin B6. They also supply trace minerals such as manganese.


Feeding onions in moderation allows chickens to enjoy these advantages without the risks of thiosulphate toxicity.

Which Part of Onions Can Chickens Eat?

All parts of an onion can be fed to chickens, but in limited amounts:

  • Onion bulbs: This is the most concentrated source of thiosulphates, so limit bulb feeding to 1-2 small slices per chicken 2-3 times a week at most.
  • Greens: The green shoots contain fewer thiosulphates than bulbs, so they’re safer to feed. But still offer them only in moderation.
  • Scraps & peels: These make good treats. Just don’t let them make up more than 10% of the diet.
  • Roots & stems: Perfectly fine for chickens but offer them as occasional snacks, not daily feed.


Avoid any spoiled, moldy, or rotten parts of onions. These can harbor toxins and bacteria dangerous to chickens.

Can Chickens Eat Onions Raw or Cooked?

Chickens can eat both raw and cooked onions. In fact, some research shows that cooking may slightly reduce the harshness of some compounds:

  • Raw onions retain more vitamin C and antioxidants. But they also have more potent thiosulphates.
  • Cooked onions have fewer antioxidants. But cooking seems to lower thiosulphate levels a bit.

Both raw and cooked onions can be fed safely as treats if proportions are controlled. Try scattering some chopped raw onions on feed or mixing cooked onion into a grain mash for variety.

What Effect Does Onion Have on Chickens?

When fed in moderation, onions provide:

  • Added nutrition: Onions supply prebiotics, vitamins, minerals, and antioxidants missing from chicken feed. This boosts overall nutrition.
  • Enhanced egg & meat quality: The antioxidants and prebiotics may make eggs and meat from chickens fed onions more nutritious.
  • Better immunity: Onion antioxidants can reduce inflammation and strengthen the immune system.

But if overfed, onions may cause:

  • Hemolytic anemia: Destruction of red blood cells leads to fatigue and breathing trouble.
  • Gastroissues: Diarrhea, vomiting, and other stomach problems.
  • Aortic rupture: The aorta can split and cause sudden death. Mostly a risk to young chicks.


Moderating onion intake avoids negative effects while allowing chickens to benefit from their nutrition.

Can Chickens Eat Onion Greens?

Yes, the green shoots of onions are safe for chickens to eat. In fact, onion greens are more nutritious than bulbs:

  • Rich in vitamin A for eyesight and immunity
  • Good source of vitamin C, vitamin K, and manganese
  • More antioxidant power than bulbs
  • Fewer concentrated thiosulphates than bulbs

Chickens can eat both young green onions and mature onion greens. Chop the greens into smaller pieces for easier eating. Feed onion greens a couple times a week as part of a balanced diet.

Can Chickens Eat Onion Scraps?

It’s fine for chickens to eat small amounts of onion scraps as treats. Some tasty, healthy scraps chickens enjoy include:

  • Outer onion peels
  • Root ends and tips of onions
  • Leftover chopped raw onion or cooked onion bits
  • Discarded parts of onions, as long as they are still fresh

Just don’t feed onion scraps every day. An occasional treat here and there is safe and allows chickens to enjoy the nutrients.

Can Chickens Eat Onion Skins?

The paper-like outer skins of onions are safe for chickens to eat. In fact, the skins contain a high concentration of quercetin. This antioxidant compound supports chicken health.

Before feeding, rinse onion skins well and chop into smaller pieces if needed. Offer skins sporadically as treats, not daily meals. This allows chickens to benefit from the antioxidants while avoiding overconsumption.

Can Chickens Eat Onion Stems?

The dried, fibrous stems of onion bulbs provide enrichment for chickens. Chewing on them is healthy beak exercise.

Onion stems contain minimal thiosulphates, so they’re safe to eat. Their stringy texture also helps clean chickens’ crops. Limit intake to a few stems at a time, a couple times per week.

Can Chickens Eat Onion Roots?

The small roots attached to onion bulbs are perfectly fine for chickens to eat. In fact, onion roots have nutritional value:

  • Concentrated inulin & fructooligosaccharides to support gut health
  • Rich in manganese, copper, and other trace minerals
  • High antioxidant content, including flavonoids

Rinse roots well and chop into smaller pieces before feeding. Offer them along with greens as nutritious onion treats.

Can Chickens Eat Onion Tops?

The green tops of onion plants can provide nutrition for chickens. Compared to bulbs, tops contain:

  • More vitamin C and vitamin A
  • Lower amounts of harsh thiosulphates
  • Beneficial antioxidants like quercetin

Chickens can eat both young onion tops just sprouting as well as larger mature onion tops. Introduce them fresh or dried as part of a balanced diet.

Can Chickens Eat Onion Peels?

The papery outer skins peeled from onion bulbs are fine for chickens to eat. In fact, onion skins are more nutritious than the flesh:

  • High in quercetin, an antioxidant compound
  • Concentrated amounts of other antioxidants
  • Rich in anthocyanins that provide color

Just don’t rely on peels as a core feed ingredient. Use them as supplemental treats a couple times a week to provide nutrition and enrichment.

Can Chickens Eat Yellow Onions?

Yes, chickens can safely eat yellow onions in moderation. Compared to other colors, yellow onions have:

  • A milder flavor and aroma
  • Lower antioxidant content
  • Lower amounts of anthocyanins and flavonoids

But yellow onions still contain healthy prebiotics and organosulfur compounds. A few slices or scraps 2-3 times a week is fine for chickens.

Can Chickens Eat Sweet Onions?

Sweet onions like Vidalias and Walla Wallas make healthy treats for chickens. Their sweeter taste comes from:

  • Higher water content
  • A bit less thiosulphates and sulfenic acids
  • More fructose than other onions

In limited amounts, these sugars and milder compounds are fine for chickens. Just feed sweet onion scraps in moderation along with other treats.

Can Chickens Eat Green Onions?

Also called scallions, green onions are a safe and healthy snack for chickens. Compared to bulbs, green onions contain:

  • Lower thiosulphate levels
  • More vitamin C and vitamin K
  • Concentrated antioxidants

Both the green shoots and white bulbs of green onions can be fed to chickens in moderation. Offer 2-3 times a week as part of a balanced diet.

Can Chickens Eat Red Onions?

Vibrant red onions add antioxidant power to a chicken’s diet. The red color comes from anthocyanins. These plant pigments offer health benefits:

  • Powerful antioxidant and anti-inflammatory effects
  • Boost immunity
  • Support cardiovascular health

Chickens can enjoy small amounts of red onions 1-2 times per week. Use them cooked or raw as a nutritious supplement to their feed.

Can Chickens Eat White Onions?

White onions are healthy for chickens to eat in moderation. Compared to yellow onions, white onions contain:

  • A stronger flavor and aroma
  • More anthoxanthins that provide antioxidant effects
  • Slightly higher mineral content

The stronger aroma indicates a higher concentration of organosulfurs. Feed white onion scraps occasionally, not daily.

Can Chickens Eat Shallots?

A type of onion, shallots offer a tasty, nutritious treat for chickens. Compared to onions, shallots feature:

  • A milder, more garlicky flavor
  • Higher vitamin C, vitamin A, and iron
  • More antioxidants and beneficial enzymes

Chickens can safely eat shallot bulbs, skins, greens, and scraps. Introduce them fresh or dried into the diet in moderation.

How to Feed Onions to Chickens

Here are some healthy ways to feed onions to your flock:

  • Dice up raw onions over feed
  • Mix cooked onions into warm grain or veggie mashes
  • Offer fresh onion greens still attached to bulbs
  • Toss peeled skins, stems, and other scraps into runs
  • Hang onion tops or braids for pecking and enrichment

Provide onions in combination with other fresh treats like fruits and veggies. Feed onion-enhanced meals only 2-3 times per week in limited amounts.

How Much Onion to Feed Chickens

When feeding onions, moderation is key:

  • Adult chickens: 1-2 slices onion or shallot 2-3 times per week
  • Baby chicks: Wait until 6 months old to feed onions
  • No more than 10% of diet from onions
  • Avoid spoiled onions or any moldy parts


Feed onions as supplemental treats, not core daily feed. Spread out onion feeding and watch for signs of anemia or stomach upset.

Can Baby Chickens Eat Onions?

It’s best to avoid feeding onions to baby chickens under 6 months old. Their digestive and immune systems are too immature to handle the thiosulphates.

Chicks also have a higher risk of aortic rupture from compounds in onions. Wait until chickens are adults before offering onions in careful moderation.

In summary, onions offer some nutritional benefits but must be fed cautiously to chickens. Use onions as occasional treats in limited amounts, avoiding overconsumption. This allows chickens to gain advantages from onions without detrimental health effects. Follow the recommended feeding guidelines when feeding vegetables to chickens for happy, healthy chickens.

Frequently Asked Questions

Can chickens eat onions?

Yes, chickens can eat onions. Onions are not toxic to chickens and can be fed to them either raw or cooked. However, onions should be fed in moderation as part of a balanced diet.

Are raw onions safe for chickens?

Raw onions are safe for chickens to eat. However, it’s best to chop or process raw onions into smaller pieces before feeding them to chickens to prevent choking hazards. Very large pieces of raw onion may be difficult for chickens to digest.

What are the effects of onion on poultry?

Onions provide some health benefits to chickens. They contain vitamins, minerals, and antioxidants. Onions may help boost chickens’ immune systems and respiratory health. However, onions can cause the eggs and meat of chickens that eat them to have an “off” flavor.

Why do chickens love onions?

Chickens likely enjoy the strong taste and aroma of onions. The sulfur compounds in onions may attract chickens to the vegetable. Onions also provide moisture and nutrients that chickens naturally crave in their diet. So the combination of the taste and nutritional value of onions make them appealing to chickens.

Can onions affect chicken eggs?

Yes, onions can affect the taste and quality of chicken eggs if chickens eat large amounts of onions. The compounds that give onions their strong flavors and odors can get transferred to eggs. This can make the eggs have an “off” or onion-like taste and aroma. It may also slightly reduce the shelf life of the eggs.