If you’ve ever picked up a bag of bargain birdseed from the store and noticed it sitting mostly untouched under your feeder, there’s probably a reason why. It’s called filler seed, and it’s not doing your backyard birds (or your wallet) any favors.
Let’s break it down.
What Is Filler Seed?
Filler seed is exactly what it sounds like: low-cost ingredients that take up space in a seed blend without offering much value to birds. The goal? To bulk up the weight and keep the price low. But birds are smart, and most of them simply kick it aside in search of something better.
Here are a few of the most common filler culprits:
❌ Cracked Corn
This one shows up in lots of inexpensive mixes. While a few birds like doves or grackles might nibble at it, most songbirds pass it right by. Cracked corn also attracts pests like squirrels, raccoons, and the occasional unwelcome rodent. Unless you’re feeding ground-feeding birds specifically, you don’t need it.
❌ Red Milo (aka Sorghum)
Red milo is one of the biggest space-fillers out there, and a total money waster! It looks like a tiny reddish popcorn kernel, but most backyard birds won’t eat it. A few wild game birds like turkeys, quail, and doves might give it a try, along with some western species like Steller’s Jays and the usual crowd of European Starlings and House Sparrows (and who wants those!). But if you’re east of the Rockies, most of it ends up tossed aside and piling up on the ground.
✅ A Note on White Millet
White millet sometimes gets lumped in with filler seeds, but it’s actually a good ingredient when used correctly. It’s a favorite of small ground-feeding birds like juncos, sparrows, and towhees. The key is to offer it intentionally and not confuse it with the outer hulls or “chaff” you might see after a flock has picked through a seed mix.
So if you’re seeing what looks like little white pieces under your feeder, it might just be the outer coating from millet or sunflower, not filler. But if you’re seeing piles of uneaten red milo or cracked corn, you’ve probably got a blend that’s more filler than food.
Why It Matters
The birds don’t eat it. You end up cleaning it up. It attracts pests. And worst of all, it keeps the birds you do want from coming back.
That’s why we keep our HappySeed Boxes free from junk ingredients. Every blend we create is customized to your zip code and feeder type, made with high-quality seed that backyard birds actually want to eat.
And since every box is blended just for you, you can request more of a certain ingredient or less of another. Don’t want millet? No problem. Have a grackle problem and need more safflower? We’ve got you covered. Just leave us a note or send us an email and we’ll take care of it.
Because watching birds should feel joyful, not frustrating.
Want to try a seed blend that’s worth every scoop?
Start your HappySeed Box here.
No filler. No fluff. Just happy birds.