To work out the right order for total mixed ration ingredients to go into the mixer, you need to think about the physical properties of what you are loading. Those include adhesiveness, static electricity, hygroscopicity or water absorption capacity, density, shape, and particle size. Each of these affects mixing in a different way.
Before going further, there is one thing worth saying plainly, because a lot of advice on this subject is written as though a single correct sequence exists. It does not. Manufacturers genuinely disagree, and the right order depends on your mixer type. In one survey of 14 mixers, six manufacturers recommended processing dry hay first while eight recommended adding grains first. So the first rule is to follow your own manufacturer’s instructions, and use general principles only when those instructions are unavailable.
The Two Properties That Matter Most
Among all the physical properties listed above, moisture and density deserve the most attention.
Moisture
Dry ingredients with small particle sizes will stick to anything wetter, such as molasses or silage. That is why dry components generally go in before wet ones, and why liquids are added at the very end. Adding liquid too early causes dry ingredients to ball up and clump instead of dispersing.
It is a little like making a cake. You start with flour because it is dry and because it makes up the largest quantity. Then come the other dry items in smaller amounts, such as sugar and yeast. Only once the dry ingredients are in the bowl do you add the wet ones like eggs and oil.
Density
The principle here is simple: heavy things sink, light things float. Corn silage is around a third denser than alfalfa silage, and a mineral mix can be two or three times denser than a protein or grain mix. Low-density ingredients with long particle length, such as hay, generally go in first, followed by high-density ingredients of small particle size that will sink down through the mix.
Order Depends on Your Mixer Type
This is the part most guidance skips, and it is the reason manufacturers disagree with each other. A vertical mixer and a horizontal mixer handle material differently, so they want to be loaded differently.
| Step | Vertical Mixer | Horizontal Mixer |
|---|---|---|
| First | Dry forages with plenty of volume, including unprocessed hay | Grains, concentrates, and liquids |
| Next | Grains and concentrates | Pre-processed forages |
| Last | Ensiled forages, then liquids | Wet byproducts, then liquids |
The reason for the difference comes down to what each machine can process. Vertical mixers are designed to handle rations built on long-stem hay, including whole round or square bales, which is why unprocessed hay can go in first and be cut down during mixing. Horizontal mixers are not designed for that. Loading unprocessed hay into a horizontal mixer increases horsepower demand and puts excess torque on the augers and gears as forage balls up around them, and balled forage delivers an imbalanced ration.
Even with a vertical mixer, many operations still process hay beforehand, because vertical mixers do not always grind hay down to the target range and loading pre-processed hay from a pile is faster and more accurate.
The Principles That Hold Regardless of Mixer
Whatever machine you run, a few rules apply consistently.
- Anything needing processing goes in first. Material that must be cut to length needs time in the mixer to get there, and loading it last means it never reaches the right particle size.
- Liquids always go in last. This prevents dry ingredients balling and clumping. Where possible, apply them through a spray bar so the liquid spreads across the load rather than landing in one spot.
- Small-inclusion ingredients go in early. Minerals, vitamins, and additives are used in tiny quantities and need the most mixing time to disperse through the batch.
- Keep wet sticky byproducts away from fine dry feeds. Wet distillers grains landing directly onto a mineral supplement will bind it into clumps rather than let it disperse.
- Watch where ingredients land. In a vertical mixer, never load directly over the centre screw, because small-inclusion ingredients and liquids can be caught on top and never blend in at all.
- Mix three to five minutes after the last ingredient. Run at the mixer’s rated speed, and resist the urge to keep going, since extra time only reduces particle size further without improving uniformity.
“When a customer tells me their ration is inconsistent, I ask about loading order before I ask about the machine, because it is usually the cheaper problem to fix. The one that comes up most often is liquids going in too early, which turns the fine dry ingredients into lumps that never break up. The second is minerals being added at the end, when they have the least time to disperse and they are the most expensive thing in the mix to waste.”
Sue Su, Marketing Director, Jummos
A Finding Worth Knowing About Premixes
Achieving a perfectly uniform mix is genuinely difficult, because the ration is made from ingredients with very different physical properties. That difficulty is why many dairy producers rely on premixes from feed mills, or make their own, so that additives, minerals, byproducts, protein mixes, and grains are thoroughly blended before they ever reach the mixer.
The assumption behind that approach deserves scrutiny. A study evaluating the uniformity of manufactured premixes found that only about half achieved a coefficient of variation within the 10 percent generally considered acceptable, while roughly a fifth of samples showed a coefficient of variation above 30 percent.
That matters because feed mills use more advanced equipment than most on-farm processing. If manufactured premixes vary that much, on-farm premixes are unlikely to do better. The practical implication is that animals may not be consuming ingredients in the proportions the ration specifies, and that heavy minerals, which are among the most expensive components, may not be evenly distributed. It is an argument for paying close attention to loading order and mixing time rather than assuming the premix has already solved the problem.
If You Have No Manufacturer Instructions
Start by finding them, since they are the most reliable guide for your specific machine. If they genuinely are not available, the following protocol is a reasonable default.
- Process long hay beforehand, unless you are running a vertical mixer designed to process it in the tub.
- If you do not need further processing of forages in the mixer, add grains or premixes first, followed by ingredients used in small amounts such as minerals and vitamins.
- Add the forages that do not require processing next.
- Finish with liquids as the final item.
Then check your work rather than assuming it worked. A well-mixed ration shows no clumps of hay, no streaks of feed, no balls of wet byproduct along the bunk, and consistent particle size from one end of the feed line to the other. If you see any of those, the loading order is usually the first thing to revisit.
Getting the Machine Right Too
Loading order can only do so much if the machine is wrong for the batch. Overfilling stops ingredients moving properly, and underfilling a vertical mixer means the material never reaches the top of the augers. Our guides to the multiple auger TMR mixer and TMR mixer sizes cover matching capacity to your herd, and our overview of the TMR mixer compares the types in more detail.
Jummos supplies trailed and stationary TMR mixers with guidance on loading and mixing for each configuration, so you are not left guessing at the sequence. Tell us your ration and your herd, and we will recommend a machine and the loading order that suits it.
Frequently Asked Questions
What is the correct order for loading a TMR mixer?
There is no single universal order, and manufacturers genuinely differ. In one survey of 14 mixers, six recommended processing dry hay first and eight recommended grains first. Broadly, vertical mixers start with bulky dry forages, then grains and concentrates, then ensiled forages and liquids. Horizontal mixers start with grains, concentrates, and liquids, then add pre-processed forages and wet byproducts. Always follow your manufacturer’s instructions where they exist.
Why should liquids always be added last?
Because liquid added early causes fine dry ingredients to ball up and clump instead of dispersing through the mix. Those clumps do not break apart during mixing, so the ration reaching the feed bunk is uneven, and the animals eating the clumps get a very different diet from the ones that do not. Adding liquids last, ideally through a spray bar that distributes them across the load, avoids the problem entirely.
Can I load unprocessed hay straight into the mixer?
It depends on the machine. Vertical mixers are designed to process long-stem hay, including whole bales, so unprocessed hay can be loaded first and cut during mixing, with careful attention to mixing time so particle length is not reduced too far. Horizontal mixers are not built for this. Unprocessed hay raises horsepower demand, puts excess torque on augers and gears, and tends to ball up around them, which produces an imbalanced ration. For horizontal machines, process the hay beforehand.
Reviewed by Sue Su, Marketing Director of Jummos, on September 15, 2026. Loading sequence guidance was checked against current dairy extension and manufacturer recommendations to keep the information accurate for farmers.