How to Add Chickens to Your Flock

It’s officially chick season, and if you're raising backyard chickens, there's one thing you need to do carefully: flock integration. As a backyard poultry keeper, I know how important it is to keep your chickens safe, healthy, and happy.

Last January, I lost half of my flock to a hawk attack. I was heartbroken and wasn’t planning to bring in any new birds. But I realized my two surviving girls needed companionship, so I decided to expand the flock. I brought home three standard chicks (Frenchy, Pepper, and Dolly) and five bantam chickens (Millie, Gladys, Betty, Nancy, and Marge).

Since I had both standard and bantam breeds, I ran into challenges and questions. Could bantams live safely with larger chickens? Would the pecking order be too aggressive? After speaking with poultry experts, I created a plan, and it worked! So I wanted to share it with you.

Here’s exactly how I introduced my new birds and made it a smooth transition.

When Can You Add New Chickens to an Existing Flock?

Wait until your chicks are at least 8 weeks old before introducing them to the main flock. I waited even longer since I had bantam chickens, which are smaller and more vulnerable.

*Important Tip!: Never place small chicks directly into a coop with full-grown hens. They’ll likely be seen as a threat, and things can turn deadly fast. Instead, wait until the chicks are nearly the same size as the existing flock. If you’re dealing with bantams and standard chickens like I was, give it even more time (around 10 to 12 weeks) and monitor closely.

Step 1: Start with Visual Separation

Use a hutch or dog crate to keep your new chicks inside the run, but separate from your older hens. This allows everyone to see and hear each other without any contact.

Not only is this a budget-friendly solution (hello, Facebook Marketplace!), it also lets your flock get used to the newbies slowly.

*Chicken coop idea: Repurpose an old dog crate or build a small “mini coop” inside your existing run for this stage.

Step 2: Supervised Free Ranging

After about a week or two of side-by-side living, let everyone free range together in your yard. Stay nearby to monitor any aggressive behavior.

Some pecking is normal as the flock establishes hierarchy, but you don’t want to see ganging up or bullying. I did this step several times before committing to full coop integration.

Step 3: Coop Integration at Night

Once they’ve free ranged together a few times, sneak your new birds into the chicken coop at night. Chickens can’t see in the dark, so when they wake up, they’ll all be roosting together as if it’s always been that way.

For the next few nights, you’ll need to physically place your new chickens in the coop, since they don’t yet know it’s “home.” After 2–3 nights, they usually learn the routine.

Bantams are significantly smaller and need extra care during integration. Tips for Adding Bantams:

• Wait 10–12 weeks before introduction
• Ensure plenty of hiding spots in the coop and run
• Monitor more closely during free range time
• Avoid integrating just one bantam; a group of 3–5 is better

I personally created little hideouts using overturned flower pots and stacked hay bales in the run for my bantams to retreat to.

How to Add a Full-Grown Chicken to the Flock

This one’s a bit different! Full-grown chickens can be added more quickly, but quarantine is essential. Quarantine Checklist:

• Isolate the new bird for 2 weeks in a separate crate or hutch
• Watch for signs of illness (sneezing, runny eyes, lethargy)
• Introduce visually before allowing contact
• Then follow the same steps: free range + nighttime coop addition
   

Diseases can spread fast in a flock, and it’s not worth the risk. Even poultry has to practice a little social distancing sometimes!

What to Feed New Chickens During Integration?

During this process, it’s important to offer high-quality chicken feed for both your existing hens and your new birds. Young chicks and bantams might require starter feed longer than standard pullets.

*Pro Tip: Use separate feeding areas to prevent bullying around the food and to ensure everyone gets the nutrients they need.