5 things you should never put in your compost

5 Things you should never put in your compost

Are you interested in starting a compost pile but are overwhelmed by all the options, or is your compost not performing as you’d hoped? Well, don’t worry, I am here to help.

Compost is amazing for your garden because it is so rich in nutrients and using your own compost can save money and reduce waste. Although it can seem daunting to start with, once you get through all the waffle and jargon, the process is really simple and forgiving – you can check out this article to help you start composting whatever your budget or space.

5 Worst things to compost

1. Tomato Plants and Foliage

Tomato plants are easy to grow which makes them the most widely homegrown vegetable, but they are also one of the most easily diseased. And this disease can easily spread throughout your compost pile. Most home compost piles don’t reach high enough temperatures to kill the pathogens and spores so they’ll be laying wait to transmit to your plants when you use the compost.

What to do with tomato plants

Option 1: Put the effort in and compost them yourself – In order to safely compost potentially diseased plants, it is crucial the pile is hot: between 55°C and 77°C. This takes more work than most are willing to do, but if you are willing, then there are plenty of articles out there to help. This one talks specifically about composting tomato plants.

Option 2: Put them in the council green bin.

2. Fish, meats, fats, and oils

By adding meat, fats, and oils to your compost you are going to attract the unwanted attention of pests and cause your compost pile to smell bad. All while slowing your pile’s decomposition right down! The reason the decomposition grinds to a crawl is that bacteria that do most of the work in a compost pile are aerobic. But, the bacteria that break down animal products are anaerobic.

What to do with meats, fats, and oils

Option 1: Try an indoor approach with a kitchen composter. You can put any food waste in and it works faster than a traditional outdoor compost pile. The Skaza Bokashi are good (I’m in the process of testing them now and will have a review up). They are made from recycled material and create compost tea which can be used as fertiliser and a natural drain unblocker. The solid material left in the bucket is an amazing compost base that is safe to add to your compost.

Option 2: Put them in the council food waste bin.

3. Carnivourus animal and human poo

Just no! Carnivorous animal and human faeces can carry harmful pathogens, parasites and infectious diseases which you don’t want to be spreading around your garden and certainly not getting anywhere near your vegetable patch.

Poo from herbivores, like horse, rabbit, cow, and chicken are safe to add.

What to do with all the poo

I own a dog and the amount of mess to clear up is astonishing. I am currently using bags, as these are the easiest but it is on my list to reduce the waste I am creating. One thing I’m considering is creating a DIY dog poo composter, let me know your ideas and experiences.

4. Plasic-coated paper

Unfortunately, some paper is coated with plastic to make it bright, colourful, and glossy. This plastic coating won’t decompose and may also have toxins that harm your plants.

What to do with plastic-coated paper

First, try reuse, magazines can be passed onto friends or sometimes places with waiting rooms are looking for second-hand magazines and books. Depending on how eagerly you’ve unwrapped your present, wrapping paper can be reused for future presents.

If you can’t reuse then repurpose it; my kids love using the pictures in magazines to create art.

5. Treated ash, sawdust, lawn cuttings

This includes painted wood, stained wood, varnished wood, pressure-treated wood, charcoal briquettes with additives, and lawn cuttings that have had weed, feed or fertiliser. The chemicals and herbicides can stay in the compost and negatively affect your plants’ health.

Bonus – 3 things you might not want to add

These things are completely bad for your compost but are worth considering before adding.

Citrus Peels and Onions

If cut up small they compost fine – all be it slower than other organic materials – but the acidity can slow down decomposition and can upset the worms you hopefully have in your compost pile. So if you want to add them, do it occasionally.

Bread, rice, cakes, donuts, pastas, and dairy products

These will decompose fairly quickly but they will attract pests and make the compost pile smell. You can reduce this by burning them deep down and adding lots of brown material on top of it to “trap” the smell.

Seed cores

Before adding vegetable scraps to the compost pile consider removing the seeds otherwise, you may get vegetables popping up in unexpected places. I learnt this the hard way when some bonus butternut squash appeared in with my tomatoes!

How to compost eggshells

How to compost eggshells

Learn the right way to compost eggshells to get the most out of them that gets you free nutrients for your plants and free pest control

During the pandemic, more people than ever are saving grass cuttings and kitchen scraps for their compost bins and turning them into the “black gold” also known as compost. The benefits are huge, but for the uninitiated, it can seem daunting. The truth is it doesn’t have to be difficult and just following this basic “recipe” for compost gets you great results:

  • 1-2 parts Greens – wet/fresh ingredients such as fruit & vegetable scraps, fresh grass, coffee grounds, tea leaves (don’t use tea bags unless you know they don’t have plastic in them).
  • 3 parts Browns – dry ingredients such as shredded newspaper, dried leaves, dried grass, cardboard, or straw.

This mix is very flexible, you really can’t go wrong just keep it in mind as you’re adding things to your compost. I keep a box of dry ingredients next to the compost so I can add a couple of hand fulls whenever I chuck in the wet stuff.

What’s the best way to compost eggshells?

Eggshells go into my top 5 best things to compost, they are a great source of calcium and can be sprinkled directly on the soil for slug and snail control.

Eggshells however will take years to break down if you just throw them on the compost without a little bit of prep. These are the steps I follow:

  1. Give the eggshells a little wash – this isn’t critical but leaving them unwashed can attract unwelcome vermin and when washed they are easier to break up.
  2. Put the eggshells in an oven try and bake for 10 mins. – I just throw them in the oven when I’m baking something else so I’m not wasting energy.
  3. Once the eggshells have cooled then blitz them into a fine powder in a blender or mortar and pestle – if using for pest control aim for small sharp pieces instead of a fine powder.
  4. Add to the compost heap or or directly to the soil. – eggshells are particularly good for tomato plants with blossom end rot.

You can break the eggshells up without baking them first but the baking step makes it easier. When broken up the eggshells will be absorbed almost immediately rather than taking years to break down.

Other composting tips for beginners

  • Mix the different materials, for example don’t chuck a huge bag of grass cuttings in one go.
  • Don’t put meat, fish, or dairy into the compost head, this will help you avoid attracting rats. Another tip is to turn the heap regularly, it provides air to the compost to stop it smelling and will detter rats.
  • If you don’t have a garden try a wormery instead. This is a stacking system of trays that you can buy ready made or have a go at making your own worm composter.
  • I forget to actually use the compost so try locating the bin near your growing area.
  • You need some moisture in the compost which shouldn’t be a problem as most green materials have loads of moisture but if you find your compost is getting a little dry then try soaking your cardboard/paper before you add it.
  • Lastly don’t fret, you’re compost is very forgiving. If you don’t get the ratios quite right you’ll still end up with compost, it just might take a little longer.
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