Compost buying guide


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Whatever you’re growing in your garden, sometimes you’ll want to give it that little something extra to really help it thrive. Good quality compost is rich in nutrients and the perfect way to keep your plants strong and healthy.

What is compost?

Traditional compost comprises primarily of peat sourced from lowland raised bogs, but over time the availability of peat from bogs has reduced. In an effort to preserve these bogs, peat-free and reduced-peat alternatives are now more common.

Peat-free composts are made up of a mixture of organic and inorganic materials such as composted bark, wood fibre, coconut fibre (known as coir), loam (a soil made mostly of sand and silt with a bit of clay) and rock wool. This combination of coarse and fine materials, infused with nitrogen, phosphates and potash, creates a balanced compost that will help your garden grow beautifully.

What sort of soil is in your garden?

Before you buy your compost you’ll want to find out what sort of soil is in your garden to ensure you get the correct type of compost to compliment it. Pick up a simple soil testing kit to help work out whether your soil is acid or alkaline as this will give you an idea of the types of plants that will thrive in your garden.

The pH of soil is measured on a scale of 1-14. This simple chart will help you work out what soil is in your garden, and what plants will grow easily in it.

pHSoil type

It’s worth remembering that the majority of plants in our gardens grow best in soil with a pH of 6.0-6.5. This is because most plants prefer a slightly acidic growing medium. However, be aware that some plants will thrive in even more acidic soil (see ericaceous compost below).

What compost should you use?

There are many different types of compost available, and which one you choose really comes down to what you’re growing in your garden.

Fine compost with low level nutrients

This type of compost is perfect for seeds and cuttings that are in their early development, as too much food will potentially kill new plants. Usually, this type of compost will have seed and cutting compost written on the bag.

Compost with increased nutrients

Use this compost for young plants that are building strength and require more nutrients to help them develop. A good compost for plants at this stage in their life is Homebase John Innes No.2.

Multi-purpose compost

Multi-purpose compost is great for use throughout the entire garden – everything from flower beds and borders to potted plants and shrubs.

Compost for hanging baskets & patio pots

Look for composts specifically formulated for hanging baskets and patio pots. These feature slow release fertilisers that will help plants flower throughout the summer. These composts also usually feature moisture retention properties that trap in moisture to help keep the plants well watered on hot days.

Grow bags

These are long plastic bags that you grow your plants in directly. Normally one bag will have enough space for 3 plants. Grow bags are perfect if you’re growing tomatoes, courgettes, strawberries or lots of other vegetables or fruits.

Ericaceous compost

This type of compost is more acidic and usually has a pH of around 5.5-6.0. Examples of acid loving plants are azaleas, camellias and rhododendrons.

Homemade compost

It’s easy to make your own compost with our great range of composters. Simply put one of these large plastic bins in your garden and empty all sorts of organic waste in to it – anything from leftover fruit and vegetables, tea leaves, coffee grounds and garden clippings – along with things like shredded paper and egg shells. Everything you put in the composter will then decompose naturally over time to create a rich compost that you can use around your garden. Creating your own compost in this way is not only cost efficient, it’s also great for the environment and can reduce household waste.

Types of compost

Top tips

  • It’s worth spending a little bit more to ensure you’re getting a really high quality compost. Good quality compost will result in great flowers and vegetables.
  • Be careful when lifting bags of compost as they can be much heavier than expected.
  • Store any open bags of unused compost in a warm dry environment to ensure it’s as good as new when you need it again.
  • Water plants growing in ericaceous compost with rain water, as the alkaline nature of tap water will reduce the effectiveness of the acidic compost. As rain water is slightly acidic, it will help keep the compost at the desired pH level.
  • If you’re making your own compost make sure you use one of our simple testing kits to check the pH of your soil before putting it on your garden. The target pH you are looking for is between 6.5 and 7 for general purpose use.

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