8 tricks for growing azaleas and rhododendrons in the shade of your garden

A large shrub covered with blossoms, like azalea and rhododendron, is always a dazzling show. Enjoy the luscious blooms of these flowering shrubs in the partially shaded areas of your garden.

Azaleas and rhododendrons are ideal shrubs for partial shade.

• They're native to woodlands where the soil is naturally acidic, so they grow best in soil with a pH below 6.
• Grow azaleas and rhododendrons near large shade trees or mix them with other shrubs in foundation plantings.
• There are both evergreen and deciduous hybrid azaleas, as well as evergreen rhododendrons in a range of sizes and colours.

Remember that azaleas and rhododendrons respond best to moderation in all aspects of cultivation: moderate light, moderate water and moderate pruning.

The common practice of putting fertilizer directly in the bottom of a planting hole can be fatal to azaleas and rhododendrons.

• Wait until the plant is established before you start feeding it.
• However, do enrich the planting hole with several spadefuls of good compost.

Azaleas and rhododendrons need a eight-centimetre (three-inch) mulch of wood chips, pine needles, bark chips, salt hay or oak leaves to keep the shallow roots cool and moist.

• Adequate moisture is critical until new azaleas or rhododendrons become established — which takes at least two years.

Once mature, they can survive moderate drought, although drought-stressed plants are more susceptible to disease, insects and cold. Help out wilted plants with a deep soaking.

• Rejuvenate old plants gradually over a three-year period, cutting back a third of the branches each year.
• Prune in early summer after the flowers have faded, to avoid injuring next year's flower buds.

Sudden yellowing of acid-loving plants, such as dwarf azaleas, hydrangeas and gardenias, could signal a drop in the plant's iron intake or a shift in the soil's pH level.

• To resolve either problem, mix 30 millilitres (two tablespoons) of apple cider vinegar in one litre (one quart) of water and pour 250 millilitres (one cup) around the plants once a week for three weeks.

To encourage blooms in acid-loving azaleas, water them every week during their non-flowering period with 45 millilitres (three tablespoons) of vinegar in four litres (one gallon) of water.

Yellowish speckling of upper leaf surfaces and black spots on the undersides of azalea leaves indicate the presence of lace bugs or thrips.

• Get rid of them with insecticidal soap spray applied on a cloudy day.