Nothing says ‘springtime’ more than the bright pop of colour that an azalea bush adds to your garden. Despite a persistent myth that they’re hard to take care of, azaleas couldn’t be easier to grow, doing well in a variety of conditions and climates.
Follow our azalea growing guide to brighten up your garden and add a smile to your face!
A member of the Rhododendron family, azaleas do well in almost any garden. Did you know that there are more than 10,000 varieties of this delightful plant? It’s true – over the years, avid gardeners have selectively bred azaleas for scent, cold tolerance, colour, and shape. As a result, no matter what colour, shape, or height you’re looking for, you’ll find an azalea cultivar perfect for your garden.
Trying to attract more honeybees to your garden? Azaleas lure them in – bees just love their nectar! Choosing from more than 10,000 varieties is difficult, but here are some of our favourite azalea cultivars:
You can buy azaleas anywhere you usually purchase your gardening and planting supplies. Every garden centre will have a wide array of azalea seeds to choose from, but if you want an even more extensive selection just head online. The Royal Horticultural Society has a wide array to choose from, with choices changing year to year.
Deciduous azaleas flower for a few weeks to a month out of every year, usually in May or June. Enjoy their spectacular blooms!
Plant your azaleas in the late spring or the early fall.
By following a few simple tips, you can grow healthy azaleas in your garden year after year.
Plant them alone – We suggest planting them alone, but mass plantings can work well in larger gardens or wooded areas. They look great as background, behind sparser conifers.
Plant in partial shade – Plant them in the spring in a cool, partially shaded area. Too much sun can scorch them, and too much shade will deprive them of oxygen.
Acidic soil – They prefer well-drained, acidic soil. If you can’t guarantee adequate drainage, it’s best to plant them in raised beds or containers.
Add compost – Compost the soil before planting in order to add vital nutrients.
Add mulch – Lay down composted pine bark mulch around the base of your azalea bush to help the water go further, maintain the right temperature, and prevent weeds. Replace annually
Add fertiliser – If you have low-nitrogen soil, add fertiliser to prevent nutrient deficiencies that can cause stunted growth.
Follow these tips to keep your azaleas healthy and thriving:
Azaleas tend to grow best in partial shade; however, the deciduous varieties will do better with more sun than the evergreen varieties.
Azaleas are prone to water stress because they have a shallow root system. For the best results, keep the soil moist, never letting it dry out completely but preventing it from becoming saturated with water (which will cause root disease). You’ll need to water sunny plantings more than shaded ones. We recommend adding 6-10 cm of mulch around the base to retain moisture.
Azaleas prefer well-drained yet moist soil that includes a lot of organic matter, which is why we recommend adding compost before planting. Water-saturated soil will cause root rot and kill your plant, so if your soil is too heavy, consider raised beds.
Aerate your soil by regularly adding composted matter. This will encourage healthy microbial and fungal activity in the soil, allowing the fine roots to more easily penetrate the soil.
All rhododendrons prefer soils with a pH between 5.0 and 6.0, but they will tolerate 4.5 pH. You’ll soon see if the pH is off, as your leaves will turn yellow with green veins.
Use soil that includes half organic material, including compost, sphagnum peat moss, oak leaves, and/or pine or fir bark fines. Keep walnut roots and clippings away from your azaleas, as they are poisonous to all rhododendrons. You can also include vermiculite, perlite, or small lava rocks.
Evergreen azaleas, in particular, do well in pots, as they don’t tend to grow as tall as the deciduous varieties. Set a wide bottomed container on pot feet for effective drainage, and line the pot with compost. Place your pot in a partially shaded area, and water it regularly to keep the soil moist. If using tap water, leave it to stand for 4-6 hours so that the chlorine evaporates before it touches the soil.
Azaleas are a resilient and hardy plant that don’t tend to be affected by pests and diseases. With just a little bit of care (such as maintaining good drainage and partial shade, and adding mulch around the base) you can prevent the following issues:
Powdery mildew – You might not notice this common fungus on the underside of your azalea leaves, but you will see pale green, red, purple or yellow patches on the tops.
Bud blast – Bud blast causes your buds to turn brown and wither, even though they remain attached.
Petal blight – Petal blight causes your petals to decay into wet, slimy sludge.
Gall – A white fungus that causes azalea leaves to become pale and swollen.
Rust – Rust causes yellow spots of the tops of azalea leaves, and pustules of orange spores underneath.
Common pests include lace bugs, thrips, and spider mites.
Here are some of the most commonly asked questions about growing azaleas.
You can grow both hardy and non-hardy cultivars of azaleas.
Azaleas prefer acidic soil, between 5.0 and 6.0 ph.
In general, azaleas will grow best in partial shade. However, certain different varieties will thrive will more sun.
Azaleas come in evergreen (also known as Japanese) and deciduous varieties. The evergreen varieties grow up to 90cm in height, making them perfect for containers or smaller spaces. Deciduous azaleas grow far taller, reaching 1.5 metres in height after a decade. They shed their leaves each autumn, are very hardy.
A lot of people believe the common misconception that azaleas are challenging to grow. In reality, if you follow the tips in this article, your azalea bushes will be healthy and vibrant, a much-cherished pop of colour in your garden.
Evergreen azaleas are smaller than deciduous azaleas, and they are perfect for small gardens and containers.
Yes, azaleas can be planted in pots and containers – see above for more information.
Azaleas bloom in May or June.
Imagine your garden looking its best – brightly-coloured azaleas, polished teak garden furniture, a softly trickling water feature, and lazily buzzing honeybees. It doesn’t have to be a dream! Using our tips above, you’ll have azaleas thriving in your garden in no time.
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SF Gate (2020). How Can I Tell the Difference Between a Shade Azalea & a Sun Azalea? [online] Home Guides | SF Gate. Available at: https://homeguides.sfgate.com/can-tell-difference-between-shade-azalea-sun-azalea-91333.html [Accessed 28 Sep. 2020].
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VanBuren, J. (2018). Are Azaleas Really Hard To Grow? [online] www.homenursery.com. Available at: http://www.homenursery.com/blog/bid/297685/are-azaleas-really-hard-to-grow [Accessed 28 Sep. 2020].
Anna is the marketing and office manager for Garden Benches – a premium supplier of high-quality wooden benches and other outdoor furniture.