Is Stale Beer Good For Plants?

I had a birthday bash last night and was left with a few bottles of opened stale beer. I did not want them to go to waste and was curious whether the beer is organic and good to use for plants.

Stale beer is not good for plants if you’re thinking of using it as fertilizer. The alcohol in the beer can harm your plants making them unable to absorb nutrients. Beer contains some protein, potassium, calcium, phosphorus, and carbohydrates. But only a small amount.

I’ve written a lot more details about why stale beer is not good for your plants. But I’ll also let you know how you can put the stale beer for good use in your garden.

What are the problems with using beer for plants?

Beer contains alcohol

The biggest problem of using beer on the plants is that it contains alcohol. The amount of alcohol is less compared to heavy drinks like whiskey but it’s sufficient to slow down the growth of the plants.

You may be able to reduce the alcohol content a bit by leaving the beer open for 24 hours or more. This helps to evaporate a bit of the beer but it does not completely remove it.

Beer only gives simple carbohydrates

Your plants need carbohydrates to make their own food and you may thing beer has plenty of carbs so this much be good for the plant.

The problem is that beer contains simple carbohydrates that get absorbed fast by the plant. So you’re much better providing good organic fertilizer to the plant instead.

The beneficial organisms in the soil need complex carbohydrates to thrive and such simple carbs won’t do much to encourage their growth and activity.

Beer contains fungi

Beer contains yeast which is a type of fungi. You may think that it’s good to add yeast to the soil as it will help the beneficial organisms in it. But the same yeast can harm the soil and even make it smell bad.

You need to be careful you don’t invite fungal diseases to your plants because of the yeast splashing on the leaves.

Beer has only minimal nutrients

You can find nutrients like proteins, potassium, magnesium, and calcium in beer but these nutrients are in small amounts. You just get 6 grams of protein in a liter of beer.

Beer also contains carbon dioxide that plants use to prepare their food. But they get plenty of this gas from the environment and don’t need to rely on beer.

It’s much better to use good organic fertilizer and compost that is rich in nutrients and helps the soil and plants develop a healthy soil food web.

Beer is expensive

Beer contains 90% water and you may think it’s good to use it for watering the plant. But it does not offer you anything significant than using water and fertilizer.

You will be wasting your money on beer for watering the plants. Even if you get the cheapest beer available, nothing beats using tap water for your plants.

How to use beer to benefit your plants?

Now you know that it’s not good to directly use the beer for the soil or your plants. But you can use stale beer in some other ways to benefit your plants or garden.

Use in compost

One of the best things you can add to your plant soil is organic compost. This material is rich in organic matter that contains a ton of nutrients for the plants. It also encourages beneficial organisms to thrive in this material which further enriches the soil texture and nutrient content.

You can make your own compost by adding layers of organic material like dried leaves, branches, straw, food waste, and newspaper to a pile. You keep adding such material and watering the pile to keep it a bit wet. It’s good if you turn the compost pile every week or so because this speeds up the decomposing process by improving the aeration of the pile.

Slowly the material starts to decompose and after a certain period of time, you get the dark, earthy, nutrient-rich compost.

If you’re distilling your own beer or wine, the raw material that remains from the process makes a great addition to your compost pile. This material will be rich in carbon and nitrogen and help improve your compost pile.

You can also add stale beer to your compost pile because the yeast will encourage the compost pile to get started. This means the yeast will be used by the organisms in the pile to break down the materials faster.

Slug trap

You can use the stale beer to trap unwanted pests that are eating up your plants. Beer is a useful tool to attract pests like slugs and snails.

If you find these pests attacking your plants, you can dig a small hole near the plants. The hole should be deep enough that an empty yogurt container can fit into it.

Fill the container with beer and let it sit overnight. The slugs and snails are attracted to the smell of beer and fall into the container. They drown in the beer and you can throw them away in the morning.

Make sure to check and refill the container every day till you get rid of all the slugs and snails in the garden.

Make a wasp trap

Wasps can eat up harmful pests in your garden so only use this if you really have a bad problem having them in the garden.

The wasps are attracted to the protein and sugar that you find in the beer. You can make a wasp trap using a 2-liter soda bottle, a pair of scissors, tape, a string, stale beer, and some dishwashing soap.

Remove the cap from the 2-liter soda bottle. Then cut the bottle in half. Invert the top portion of the bottle and insert it in the lower half so it becomes a funnel.

Join the two halves at the top using tape. Make two holes at the top so you can insert the string to create a handle. This will help you hang the trap several feet above the ground and attract the wasps.

Finally, put the stale beer and a few drops of soap into the lower part of the soda bottle. Make sure to leave an inch from the top of the funnel. The wasps will enter the funnel in search of food and drown in the liquid.

You can then dispose of the wasps in a garbage bag or bury them in the ground.

Use in lawn fertilizer

We discussed that beer has a few nutrients that could be beneficial for the plants but nothing that makes it a must for the plants. You can use it as fertilizer to grow a lush lawn though.

You need to mix a bottle or can of stale beer with ammonia, organic dishwashing soap, molasses, and lawn food to get a homemade plant booster.

When you spray this mixture on your lawn, the nitrogen from ammonia helps the grass grow thick and tall. The dishwashing soap acts as a surfactant which helps the nutrients from the lawn food stick to the grass and helps it absorb the nutrients.