Everything You Need to Know About Azaleas

The azalea is one of the most popular flowering plants: indoor varieties produce lush heads of blooms in winter, when colour is in short supply, while garden azaleas turn into clouds of pink, orange, yellow and white in spring. Here are the main types of azalea, how to care for them and what to keep in mind.

View full-size photo

What an azalea is

Azaleas belong to the genus Rhododendron in the heather family; they used to be classed as a separate genus, and the name "azalea" has stuck in gardening. The wild ancestors of indoor azaleas grow in China and Japan, where they have been cultivated for centuries, including as bonsai. Azaleas became fashionable in Europe in the 18th and 19th centuries, and today there are thousands of varieties.

In Ukraine, the yellow azalea (Rhododendron luteum), a deciduous species with fragrant yellow flowers, grows wild in Polissia and is protected.

Types of azalea

• Evergreen azaleas — including the indoor Indian azalea (Rhododendron simsii) and Japanese azaleas (R. obtusum and hybrids), with single or double flowers in white, pink, red, coral and lilac.
• Deciduous azaleas — garden hybrids such as the Knap Hill and Exbury groups, and the yellow azalea. Their leaves colour beautifully in autumn, and in spring the shrubs are covered in bright, often fragrant flowers.

View full-size photo

Caring for an indoor azalea

• Keep it cool. The secret to long flowering is 10–15 °C. In a warm room near a radiator an azalea soon drops its flowers and leaves.
• Light. Bright and indirect, without direct sun.
• Watering. Never let the root ball dry out, not even for a day. Use soft rainwater or water that has stood; now and then you can soak the pot in a bowl of water for 15–20 minutes.
• Soil. Acidic only — use ready-made azalea and rhododendron compost.
• After flowering. Remove spent flowers, repot if needed and put the pot outdoors in shade for the summer. To set buds in autumn, the plant needs cool conditions of around 10–12 °C.

View full-size photo

Azaleas in the garden

Deciduous garden azaleas are hardy to −25…−27 °C and grow well in Ukraine. They need partial shade or morning sun, shelter from wind, moist acidic soil with peat and pine needles, a mulch of pine bark and watering with soft water. Feed them with rhododendron fertiliser in spring and early summer.

View full-size photo

Symbolism and safety

In Japan and China the azalea symbolises femininity, care and moderation, and in Europe a flowering potted azalea is a popular Christmas and Easter gift.

Important: every part of the azalea — leaves, flowers and nectar — contains grayanotoxins and is poisonous to people, cats, dogs and other animals. Never use azalea petals in home remedies, and keep the plant out of reach of children and pets.

FAQ

Why is my azalea dropping its flowers?

Usually because of warmth, dry air or dry soil. Move it somewhere cool and bright and water it regularly.

Can an indoor azalea be planted in the garden?

The Indian azalea won't survive a Ukrainian winter in the ground, but it can spend the summer outdoors in its pot.

A potted azalea makes a lovely winter gift: choose from our potted plants with UFL delivery in Kyiv.

Author: Maria Svitlovir

Graduated from Taras Shevchenko National University of Kyiv, Institute of Biology and Medicine (2001). BSc in Biology, MSc in Horticulture. Writes about plants, works at a garden centre selecting and repotting plants, and contributes to plant reference guides.

About the author →