BEER and SPENT GRAINS as Fertilizer and Soil Amendment


Beer from a bottle or can is not highly beneficial to the edible garden as a fertilizer or soil amendment. The yeast is dead in many bottled beers and the sugar does little to excite or feed microorganisms. Generally, I am not convinced that adding straight sweets to the soil is a good practice for my vegetable garden.

Beer can help a garden grow

Then why might beer be good for the garden?

There is a by-product of the beer making process that you can turn into an asset. If you live near a brewery, or brew yourself, you can recycle the spent beer grains into your compost. Beer grains are a protein-rich, fibrous mash – the tough leftover hulls, seed parts and plant tissue. Spent grains contain nitrogen and a texture that can help fluff up the pile.

Where do I find spent beer grains?

Many large companies including Craft Brewing Company give away their spent grains to farms and agricultural organizations for use as livestock feed and a compost medium. If you have friends that brew at home, you might actually be doing them a favor by recycling the waste.

Spent grains can also be used in baked goods such as bread, pizza dough, cookies and even dog biscuits! So you might find there’s a bit of competition for spent grains with their new found popularity.Add nutrients to compost with beer grains

Which plants may benefit from spent beer grains?

I got my hands on some spent grains and immediately dried them to prevent them from going sour on me. Unfortunately rain was in the forecast and I had to take them inside. My family will not let me forget just how gross the garage smelled during those three thunderous days.

Recycling beer grains and using them in a garden

Once dry, I spread it out as a mulch and top dressing around kale and Swiss chard. The goal is to keep moisture in and provide a natural, gentle boost of nitrogen.

My favorite way to recycle beer grains is in the compost heap.

Combine spent grains with…

In the compost, combine with lots of brown materials such as hay, straw and old leaves, to reduce odors and speed decomposition.

Growth with beer grains

Spent Beer Grains for Compost Recipe

If you already have a compost pile in full swing, add the spent grains and the same amount or more of carbon-rich materials such as paper, straw and dried leaves. Make sure to mix the ingredients well and fluff up the pile. The more integrated the grains and balanced the compost pile, the less stinky the pile will become and the less likely you will be visited by wild animals. If you live in an urban area, odor control will be much more important to you, and your neighbors.

Keep the pile moist like a wrung out sponge – not wet because the grain mash already contains plenty of water.

If you’ll be creating a new compost pile, add some soil from your yard to introduce microbes into the mix.

Spent Beer Grains as Worm Food

While I was experimenting with worm food I tried adding spent beer grains into the bin. I combine it with other scraps and layer the slurry in between moist cardboard. The worms seem to love it.

Spent Beer Grains Quick Tips

  • It’s important to keep the beer grains covered in a worm bin to prevent a fly problem. Covering food scraps with a few inches of shredded cardboard is always a good practice.
  • Spent beer grains will start spoil in a few hours if left in a bucket or thick mass, especially so in warm weather. Freeze them if you can’t use them right away or spread them out on a hot surface in full sun if you want to dry them for storage.
  • Spent beer grains combined with straw make a great medium for growing mushrooms.
  • Breweries also use materials like paper filters and diatomaceous earth during processing. Diatomaceous earth is finely ground fossilized shells. Both the filters and diatomaceous earth can be composted.