The best compost for house plants – a comprehensive guide

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House plants are fantastic at bringing the outdoors in, providing a welcome boost of nature indoors. But you need to make sure they’re getting the right supplies: of water, sunlight and compost. This can make all the difference between a happy plant and one that is struggling.

In this comprehensive guide, we’ll look at the best composts for house plants, what to look for when choosing a compost, and how to use compost for blooming good plants. Let’s get started!

Types of house plant compost

You probably spent a lot of time choosing where you live. And, as a good plant parent, you need to do the same for anything you put in a plant pot!

There are many types of house plant compost, from general-purpose to specific formulas. Some of the most popular are:

• Bio-compost – made from food waste with a mega meal of nutrients

• Compost for acidic-loving plants – these include asters, begonias and coleus

• Cactus compost – cacti thrive in an alkaline soil. Cactus compost is alkaline and contains plenty of nutrients for healthy plants.

• Flower compost – a general purpose compost that is good for most plants. It’s a good all-round compost for indoor plants.

• Organic potting mix – a general purpose compost for potted plants. It’s usually a combination of compost, perlite and vermiculite.

• Potting compost – a compost specially formulated for potted plants.

Spotlight on potting compost for house plants

It’s best to opt for a compost suitable for house plants. Something which retains moisture, drains easily and feeds your plants. We offer:

Houseplant compost – includes six months of slow release fertiliser for luscious green leaves, strong stems, and a bumper display of flowers.

Cactus compost – with added grit and sand and larger coconut fibres to stop these water-sensitive plants from drowning in too much water.

Orchid compost – using evenly chipped coconut shells and coconut coir husk chips.

Citrus compost  – with the perfect mix of nutrients for your prized orange, lemon or citrus plants.

Can you use multipurpose compost for house plants?

It can be tempting to just grab a scoop of outdoor gardening compost and pop it in a house plant pot. But this short-term gain may lead to long-term pain.

Most multipurpose compost is just too high in nutrients for house plants. Remember, a house plant doesn’t have rainfall to wash away excess nutrients. Overfeeding a plant can lead to brown leaves, stunted growth or even chemical burns from the salts in the compost.

Peat free house plant compost

Peat is made from decomposed plants and so provides a huge carbon sink for the planet. Ripping it up for gardening has a huge impact on biodiversity and the climate. Plus peat compost tends to settle in pots. As it compacts downs, it can starve plant roots of oxygen.

But there are loads of peat-free compost mixes out there, with coco coir being a great choice for the environment. It’s made from the ‘bits’ from coconut husk fibres which would normally go to waste. Plus it only takes a coconut tree between 3 – 8 years to grow coconuts, and they live up to 100 years. During that time, it grows by converting carbon dioxide from the atmosphere.

Spot-on for smaller spaces

We compress our coco coir compost, delivering it in cardboard boxes rather than plastic sacks. You then add water and fluff it up as and when you need it.

Our compost blends are inert, sterile and dry. So they can be stored wherever you have space. This could be in a kitchen cupboard, in a basket in your lounge or in a hallway cupboard.

How to get rid of compost flies in house plants

So you want to bring nature inside, but not all of it! Small, black flies can be mistaken for fruit flies. But if they’re hanging around your potted plants, they’re more likely to be fungus gnats or sciarid flies. As well as flying about creating a horror film vibe, they love to lay their eggs in compost. And the larvae that hatch adore munching through plant roots. To prevent them:

• Don’t use home-made compost in your plant pots.

• Water less often so the compost is drier. This discourages egg laying.

• Add a 1cm layer of gravel mulch on top of your compost to create a barrier to stop egg laying.

• Spray the plant with soapy water in the evening to dislodge flies and eggs.

Breaking the compost fly cycle

So you got rid of those pesky compost flies. Good job! Now you need to break the cycle by re-potting your plant in fresh compost. Preferably in a compost that will keep them away.
Traditional ‘wet’ compost with rotting material encourages flies to breed and lay eggs. But all our coco coir blends are guaranteed free of pests and flies. This is because fungus gnats (Sciarid fly) can’t survive the coir compression process.

Our composts also create an inhospitable place for eggs to live. The coconut oil present in coco coir mix also repels fungus gnats.

Tips from the ‘Green Gardeners Guild’ online advice library

Want more tips about growing with coco coir? Take a look at our helpful blogs:

Potting soil for indoor plants

How to prepare coco coir: garden use vs indoor plants

How to care for houseplants this winter

Is your home a heaven of house plants?

Do you raise your plant babies on Coco & Coir? We’d love to see the results! Share your photos and tag @cocoandcoir on Instagram. We’ll credit you for any images we use and you’ll also be in with a chance to win some Coco & Coir goodies for your sustainable garden.