Gardenia vs Azalea: What Are Their Differences?

Written by Heather Hall
Published: October 4, 2022
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The lovely gardenia is often confused with the azalea, as the white and yellow varieties do look very similar. They both have wonderful benefits, such as fragrant blooms, early spring flowers, and shiny dark green leaves. They are both a favorite food of ants and bees as temperatures warm up in the spring, making them a good choice for the insect conservationist. There are also quite a few differences, which we will discuss here.

Comparing Azalea to Gardenia:

Potted azalea flower macro background

Azaleas are most often used as foundation plantings for a splash of color.

©Anastasiia Immortal/Shutterstock.com

CharacteristicGardeniaAzalea
Scientific NameGenus RubiaceaeGenus Rhododendron Deciduous azaleas belong to the subgenus Pentanthera; Evergreen azaleas belong to the subgenus Tsutsusi.
Area of OriginChina and JapanJapan and Korea
SizeUp to 8 feet tall and 5 feet wideWide range of sizes from 6 inches to 15 feet tall.
ShapeOval shrubMany shapes, from sprawling to oval shrub to vining varieties.
Time of floweringMid-SpringEarly Spring
Flower colorWhite or yellowWhite, yellow, pink, orange, purple, fuscia
USDA hardiness zonezone 7-11zone 4
Sun or shade?Part sun to full sunPart shade
Flower description2-5 inch blooms. Single or doubleFunnel-shaped, 2-lipped. 5-6 stamens.
Leaf descriptionGlossy dark green. Evergreen above zone 8. deciduous at colder temperaturesSoft pointed leaves. deciduous
Scented?Strong scent, often used in perfumeMedium scent, also has unscented varieties.
Toxic?Non-toxic, used in tea and wineAll parts of the plant are toxic
When to plantPlant in fall or early springPlant in early fall or late spring
Soil requirementsPrefers acid soil, moist but well-draining with mulchPrefers acid soil, moist but well-drained with mulch.

Key Differences Between Gardenia and Azalea

The key differences between gardenias and azaleas are description, hardiness zone, toxicity, and flowers. Gardenias are classified differently from azaleas, belonging to a different plant family and genus. While there are several similarities, azaleas are most often used as foundation plantings for a splash of color, and gardenias are most often used as a large border plant due to their large size.  

Let’s go over all of these differences in more detail now.

Gardenia vs. Azalea: Description

The gardenia grows only as a large ovular shrub.

©iStock.com/wichatsurin

At first glance, the gardenia and azalea can be hard to tell apart, especially if they both have white flowers. But there are a few easy ways to tell them apart.

The gardenia grows only as a large ovular shrub. The azalea can get large too, but most species you will find growing 2-3 feet and in a sprawling fashion. The gardenia only comes in a waxy white or pale yellow bloom, while the azalea can be bright white, bright yellow, pink, orange, or purple. If you see a pink or orange flower, it is definitely not a gardenia.

The leaves of the gardenia are very dark green and shiny. The azalea leaves are not shiny, soft, and pointy to the touch.

Gardenia vs. Azalea: Hardiness zone

Tree bonsai of Japanese azalea in a pot on a table in the garden.

Azalea prefers a partly shady environment with acidic, moist soil.

©irinacapel/Shutterstock.com

The gardenia is not cold tolerant. It likes a warm, sunny place in the garden with nice acidic soil of a 5.5 ph and moist, well-draining soil. It is hardy to USDA zones 7-11. If you are in zone 8+, the gardenia will be an evergreen shrub. If you are below zone 8, the gardenia will lose its leaves every year.

The azalea is a tougher cookie, enjoying darker, chillier climates. It prefers a partly shady environment with the same acidic, moist soil as the gardenia. The azalea is hardy to USDA zone 4 and is a fully deciduous shrub.

Gardenia vs. Azalea: Toxicity

Gardenias are often planted specifically for the large, strong-smelling blooms, which last a long time indoors after being picked.

©iStock.com/ANCHASA MITCHELL

The gardenia is fully edible, with the blooms often used as wedding cake decor, salad toppers, gourmet tea, and fine wine. Some people even make pickles out of green flower buds.

On the other hand, the azalea is fully toxic, with every part of the plant being poisonous. Bees that regularly dine on pollen from azaleas produce what is known as mad honey. Consuming the honey or any part of the azalea plant causes confusion, low blood pressure, and irregular heart rhythm. These symptoms could be life-threatening. Gardeners should take special caution with children or pets.

Gardenia vs. Azalea: Flowers

White azalea in a brown flowerpot on the windowsill blooms profusely

The azalea flower is rather delicate, with single petals arranged around 5 long stamens that damage easily.

©Witchitas/Shutterstock.com

The gardenia flower is large with either single or double petals. It is 2-5 inches across and lasts a long time in a vase. The double varieties look a lot like a rose flower. Gardenias are often planted specifically for the large, strong-smelling blooms, which last a long time indoors after being picked.

The azalea flower is rather delicate, with single petals arranged around 5 long stamens that damage easily. They last one day in a flower arrangement or centerpiece. Azaleas are planted with garden design in mind. They provide continuous spring color for the flower bed and are a welcome splash of pink or orange after a long gray winter.

Summary of Gardenia vs. Azalea

Gardenia bouquet in the glass of water and gardenia in the wicker basket, all of them put on the wooden table.

The gardenia plant does well in shaded areas and is non-toxic.

©Lapha.R/Shutterstock.com

As you can see, there are a lot of similarities as well as many differences. If you have small children or pets left alone in the garden, the non-toxic gardenia is the better choice. Azalea would be the best option if you are looking for a broader range of colors and sizes.

Another consideration is the growing requirements. If you don’t have a shady corner and need a flowering shrub that will receive full sun for at least 4 hours per day, the gardenia is the shrub for you. If you live in a northern climate that receives many hours of shade daily, you are looking for the azalea.

When selecting plants, size is certainly an issue. Suppose you have space for a gardenia that will grow to 10-15 feet tall by 5 feet wide, then you should definitely plant this strong-smelling show stopper. If you are looking for a plant that you can place in larger quantities along a foundation or island bed that will stay under 4 feet tall, the azalea will fit your design best.

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The photo featured at the top of this post is ©


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About the Author

Heather Hall is a writer at A-Z Animals, where her primary focus is on plants and animals. Heather has been writing and editing since 2012 and holds a Bachelor of Science in Horticulture. As a resident of the Pacific Northwest, Heather enjoys hiking, gardening, and trail running through the mountains with her dogs.

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