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Ericaceous compost – How and when to use it

Last updated on March 23rd, 2022

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You’ve probably heard of the term ericaceous compost, but what does ericaceous actually mean? What does it consist of and how is it used in your modern garden? This article will answer all of that and more.

If you have plants that grow in acidic soil and you want to grow them in pots, you will need to use ericaceous compost. It is worth noting that most plants (which include Rhododendrons, Azaleas, Blueberries, Heathers and Camellias) that need acidic soil also prefer a more shaded area and the sun can often cause the flowers to turn brown when exposed to direct sunlight. This often makes them perfect for more shaded areas for the garden.

When you start about planting rhododendrons you need to select a site that will be conducive to long-term growth and success for your rhododendrons. This should be a location in your garden that offers dappled shade and it's somewhat sheltered from cold winds in winter.

Defining ericaceous compost

As explained, ericaceous compost is acidic compost. It is a specially formulated compost that has a balanced nutritional profile specifically for plants that need highly acidic conditions or low levels of pH. It is a wonderful way to offset highly alkaline conditions and a must when growing plants that need acidic soil in containers and pots. 

How to use ericaceous compost

If you use an at-home pH test kit on the soil in your garden and it reveals that you have a very high pH level or highly alkaline conditions, but you really want to feed and nurture plants that prefer acidic conditions, you may be able to mix in some ericaceous compost to help compensate. However, this is something you would need to do frequently because the soil will quickly revert back.

As mentioned, a better way to grow plants that need acidic soil is to grow them in pots instead, this also gives you a chance to place them in shadier areas in the garden too. 

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It will work significantly better for you if you have mildly neutral or just barely alkaline soil, assuming you are integrating the ericaceous compost directly into the ground. If you have highly alkaline soil, on the far end of the pH scale, you are better off growing your favourite acid-loving plants in a container or a pot comprised primarily of ericaceous compost.

Even if you already have somewhat acidic soil and you want to grow acid-loving plants, these plants don’t like lime. You can always add some ericaceous compost to not only feed them but to regulate moisture by using it as a mulch too. 

What plants need ericaceous compost?

There is a wide range of plants that prefer this particular type of compost. Any plants that need an acidic pH level can benefit. This makes it particularly suitable for plants that prefer acidic soil like Rhododendrons, Azaleas, Blueberries, and Camellias. Many gardens today feature Blueberry bushes and they are also well suited to growing in pots too. Whether you are growing in your garden directly or in containers, you can add ericaceous compost to give some low pH benefits to your favourite specimens.

There is a wide range of plants that prefer this particular type of compost. Any plants that need an acidic pH level can benefit. This makes it particularly suitable for plants that prefer acidic soil like rhododendrons, azaleas, blueberries, and camellias

Each of these plants needs the right level of vitamins and low levels of lime in the soil. Too much lime and high levels of alkalinity will bind the iron and other nutrients as it becomes insoluble or ‘locked up’ and the essential nutrients that acid-loving plants need to survive. In which case, your plants will perform very poorly and at best you’ll get very weak yellow leaves. To help ensure your ericaceous plants perform well in the right soil, plant them in an isolated area with acidic soil, regularly adding ericaceous compost to help them thrive.


Keep a home pH testing kit handy because your soil will naturally revert to its original levels be it highly alkaline or highly acidic so you’ll have to test on a regular basis. Basically, anytime you change or rotate your crops or plants, just make sure that you regularly have the levels your plants need. 

Where to Buy

J. Arthur Bowers Ericaceous Compost, 50 litres Ericaceous compost is available from by clicking here

You can find ericaceous compost at almost all nurseries or garden centres. Whatever brand you choose just make sure that you re-pot your plants if they are grown in containers every few years because this compost will naturally lose its nutritional value and structure over time. Your plants will thank you if you give them some ericaceous fertiliser in conjunction with the compost every spring or whenever they start to grow again.

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