You want to compost it first ;)

If we have milk that is going bad (we hardly drink the stuff--I only use it when I down my raw eggs or on cereal), we go ahead and use it in the compost or on the garden.

If there's a significant amount of it, I dump it into the compost.

If it's just a little, I dilute it with a water and use it to water plants.

The plants haven't complained yet.

How much milk do you have? A little bit's easy: just dilute it and water it in, but I'd run large quantities through the compost; raw milk tends to be high in fat which isn't great directly in the soil.
Raw milk and baking soda spray is an excellent powdery mildew control.

If I have any milk scraps, they compost.

Raw milk will have a goodly amount of fat in it that will be difficult for the Soil Food Web to digest, and that is one of the reasons many sites that talk about composting do not recommend composting milk. The same would apply to your garden and while milk does have some good protein those fats get in the way of getting it to your plants. A small amount might not be a problem but a large amount would tend to spoil and smell something awful before being digested by that Soil Food Web.

Thank you everyone for the advise! While other articles taut its benefits, you all have brought up the unfortunate reality of its disadvantages. I liked the idea of "feeding" the soil bacteria, but it didn't occur to me that the milk fat would actually impede that very process. So, thanks again for your help.

The soil food web is a very different population than a compost food web, though they share inhabitants. The primary reason people don't compost animal matter is because the smells created in that process attract other unwanted pests, like rats and bears; and it sometimes annoys the neighbors. Eventually all living matter will decompose.

Here is a link that might be useful: The nasty bits

shebear,
I'll happily pour out leftovers on the garden, but I'd think harder about using lots of milk, often.

I am just wondering why 'raw' milk is specified. Is it easy to obtain raw milk in the US? And if there were any benefits from using milk as a fertiliser would it make any difference if it were raw or not?

It can be difficult to obtain raw milk in the USA, although some state public health people are starting to allow such sales. There is some evidence that pasturizing milk changes it and reduces the nutrient value, but the potential for diseases from raw milk still concerns many of the public health people.

Perhaps docmoo's name gives us a hint? A large animal veterinarian who works with cattle would probably have access to a lot of raw milk :)

Wow this has been fun! Yes, retired Vet and I married a Dairy Farmer, and have now taken up flower gardening. We are 4 generations on this farm (and yes, I still name every cow). In general, I don't recommend folks drinking raw milk because 1)you may not know how clean the barn is ( we are a Grade A dairy), thus you don't know what else has been splashed into that fresh bucket and 2)it is posssible that you have not been exposed to enough pathogens in your life to have immunity to whats on a farm/ out here in the real world! ex. the vast majority of asthma-suffering children have never even been exposed to dirt! Folks that have been drinking the real deal all their lives (unpasturized, unhomogenized, unaldulterated w/no antibiotics or hormones)don't have any ill side effects from drinking it. BUT, Back To The Thread ... Since I have all this "black gold" composted manure I don't otherwise compost, and I can skim off the cream if its the fat that is the problem, and I can dilute it even more with water ... so sincerely, what other recommendations do you have for me? is using raw milk as fertilizer truly wisdom? Thank you all !

I have no problem getting raw milk. It's across town at an organic dairy. They test regularly and have beautiful animals that remind me of my grandfathers cattle. A man before his time. The cost is rather steep though but it's some good milk.

I drink raw milk. It's waaaay too expensive for me to tip on the garden, but it sounds like your situation involves having plenty!
Maybe you could tip milk onto your composting manure?
I have no experience using large quanities on the garden, but I imagine even after skimming there'd still be a bit much fat to use lots of milk. I also don't know what the effects of heavy applications of a high-protein product would be on the soil.

I think you will be able to tell if you're adding too much to the garden. The smell of spoiled milk might be a clue.

If that happens, you might consider a compost pile with very low N ingredients like a pile of sawdust to pour it into. And turn it regularly to make sure it doesn't go anaerobic on you. THAT would be unpleasant.

Wouldn't it be put to best use for raising calves?

bi11me, YES ... in fact I'm feeding 12 calves right now; but the reality is that my girls always give more milk than my babies can eat before it starts to go bad! :)