Ericaceous plants are a popular addition to a garden, injecting bright, bold pops of colour, luscious, leafy greenery and even delicious fruits. But what exactly are ericaceous plants, and how do you successfully care for plants within the ericaceous family? To the novice gardener, the name “ericaceous” may seem scary, and suggest that these plants are exotic and tricky to care for – but this isn’t the case. With a few simple steps, you can easily incorporate ericaceous plants into your garden design! Here, experts at plant fertiliser brand Phostrogen® demystify ericaceous plants and share their top tips on how to care for them.
Identify ericaceous species
Deriving from the Latin word “Ericaceae” meaning “to flee from chalk,” “ericaceous” simply means that these plants prefer a more acidic soil to most. Ericaceous plants belong to the heather family, so there is a huge variety of plants out there – in fact, it is estimated that there are over 4,250 different species, so you probably already have several ericaceous species in your garden without even realising it!
Popular flowering ericaceous plants include rhododendrons, azaleas, camellias and hydrangeas, and shrubs like holly, juniper and ferns are also acid-lovers. Many edible plants, such as blueberries, cranberries and raspberries, are also considered ericaceous, so you may be surprised by just how many much-loved plants prefer acidic soil! As such, it’s important to do your research before investing in new additions, and always read the care instruction that come with your plant.
Test your soil
Soil texture is an important factor to consider for growing plants, and is defined by the level of sand, silt and clay within the soil make up. Importantly, soil texture can also influence its acidity. Sandy soils do not hold nutrients as well as clay soils so alkaline nutrients such as calcium tend to be washed out more easily, therefore making the soil more prone to being acidic. On the other hand, you can also have chalky soils which have a very high level of limestone or chalk present, which means that they are not suitable for ericaceous plants as they are very alkaline. The presence of acidic nutrients such as sulphur and iron can also increase the soil acidity, so there is lots to consider!
The key to caring for ericaceous plants is to identify what type of soil you have and how acidic the soil is. Acidity is measured using the pH scale which uses a scale between 1-14 – the lower the pH, the more acidic something is, the higher the more alkaline. A reading below 7 is considered acidic and above 7 is considered alkaline, while 7 itself is neutral.
It is also worth mentioning that pH is measured on a logarithmic scale, which that means a pH of 4 is actually ten times more acidic as a pH of 5 and a hundred times more acidic than soil which has a pH of 6.
Planting and watering
When planning what you’re going to plant where, always keep in mind the soil’s standard pH level so that you match the plants suitability to the soil pH. Ericaceous plants prefer a pH of between four and five, as they love acid-rich compost and hate lime. If you try to grow ericaceous species in alkaline or lime-rich soils, they will produce yellow leaves, known as lime-induced chlorosis, which will ultimately lead to stunted growth, lack of flowering and eventually the plant will die.
It is also a good idea to group ericaceous plants together to ensure the compost level is suitably acidic for all species, and to make caring for them effortless! Ericaceous plants are great for growing in pots, as you can control and increase the acid levels in a container more easily than in beds and borders. If you would like to grow your ericaceous plants straight into the soil but don’t have a suitable pH level in your garden naturally, dig out a large enough hole, line the edges with a sheet of plastic with drainage holes, and add a specialist ericaceous compost to plant them into.
Most ericaceous plants prefer dappled shared and indirect sunlight, so make sure you position them out of direct sunlight or you risk their beautiful flowers turning brown. Many also have shallow roots, so require regular watering as they can dry out quickly in the summer! Of course, each ericaceous plant has its own requirements, so always read the care instructions of each species before deciding on the best position for it in your garden.
Don’t forget to fertilise
As well as using a specialist ericaceous compost, it is vital that these plants are fed using a specific fertiliser designed to help acid-loving plants thrive. General plant fertilisers, like Phostrogen® All Purpose Plant Food, will provide the balance of nitrogen, phosphorus and potassium that all plants require, however a specialist fertiliser like Phostrogen® Ericaceous Plant Food also contains extra added iron and sulphur to help acidify the soil. This slow releasing formula helps ericaceous plants produce more blooms and richer, greener leaves whilst preventing yellowing.
To fertilise your soil before planting, simply mix the granules into the compost and mix together well approximately seven days prior to planting, then plant your flowers or shrubs and water well. To fertilise established plants, sprinkle the required amount of granules evenly onto the top of the soil and gently work in, watering thoroughly after each application. What’s more, Phostrogen® Ericaceous Plant Food is approved for organic gardening by the Soil Association, and is pet and child-safe.
For more gardening advice, visit www.growwithphostrogen.co.uk.