Getting it right for ericaceous plants


Ericaceous plants are plants that need acidic soil. They include Azaleas, Camellias and Rhododdendrons.  The good news is that most soil in Scotland is naturally acidic. However, to ensure you have the best soil conditions when you want to start planting, you’re best to buy some ericaceous compost. The compost is a mixture of peat, green waste and some fertiliser. For containers you should add perlite or grit to the mix to ensure good drainage.


Don’t plant ericaceous plants too deep. The rootball should be just below the surface. If you bury the rootball, you may kill the plant.

Ensure the plant is well-watered (but allowed to drain) before planting. Mix some compost into the existing soil as a planting medium. Soil should be firmed up around the roots but do not stamp on the rootball.


Water the plant in its pot thoroughly, leaving to soak for a few minutes. Ericaceous plants will not thrive if planted too deeply so be sure to plant to the same depth as the compost in the container, barely covering this with the lightest layer of soil.

Place the plant in its planting hole and then firm in lightly. If necessary, particularly with a larger plant, drive in a stout stake away from the root ball and tie the plant to it.

Finally, water the plant by giving it a thorough soaking at the roots.


Most ericaceous plants prefer the dappled shade and shelter of other trees and shrubs and are also useful subjects for a sheltered North facing border. They are tolerant of more sunny exposures as long as the soil remains moist.

But note – rhododendrons don’t grow flower well under shade. Good trees to grow with rhododendrons: Japanese maples, flowering cherries, Sorbus, Crataegus (hawthorn), Eucryphia, conifers: pine, larch, spruce (Picea), firs (Abies), cedar. Plant dwarf rhododendrons and evergreen azaleas in full sun. Deciduous azaleas, larger hybrids and species can take some shade.


You need to remember to water new plants during the first growing season and during very dry weather otherwise the fine roots will suffer. Should any weeds spring up, remove them by hand as hoeing and forking too close to the plants may damage the roots.

An annual mulch of peat, leaf-mould, pine needles or composted bark is a good boost for the plants. Spread it in a 1-2 inch band 6 inches from the base of the plant. Don’t mulch too close to the stem of the plant as this may cause the bark to rot. You can pop ona very light application of blood, fish and bone in May only but avoid any other fertilisers

After flowering, the larger flowers of rhododendrons, azaleas and camellias can be dead headed by carefully breaking out the truss of seed heads before the leaf buds start into growth, but take care not to damage these new buds.

If you would like some advice on ericaceous, or any other type of plant, pop in and see us!