beautiful rhododendron

What Type Of Soil Do Rhododendrons Like?

Rhododendrons are native to Asia, North America, Australia and Europe. There are over 1,000 species of this plant and they are widely cultivated for their beautiful and fragrant flowers with ornamental leaves. Understanding what type of soil rhododendrons like is essential if you are planning on growing these beautiful plants.

The flowers have a funnel, trumpet, bell and tubular shape, and are the national flower of Nepal.

Is a Rhododendron edible?

Even though Nepal enjoys the sour taste of the plant, it isn’t all safe to consume as some varieties can be harmful to humans as well as animals, so it’s best to be safe and not eat any at all. Due to this, it is also wise to avoid displaying in a kitchen or near food.

Rhododendrons belong to the heath family. They grow in cool climates and prefer cool and well-drained soil. You can find the Rhododendron in the mountains, coniferous and temperate forests as well as tropical rainforests.

They are cultivated due to their beauty and fragrant flowers, and also, their ornamental leaves. There are approximately 2800 new varieties of Rhododendron that are available all over the world.

What are Rhododendrons?

This is a plant meaning “red tree” which refers to the red flowers. They range from evergreen to deciduous and from low-growing ground covers to tall trees.

The leaves of a Rhododendron are usually thick and leathery. The flowers may or may not be scented and are usually tubular to funnel-shaped and occur in a wide range of colours – blue, white, purple, yellow, pink and scarlet.

They are simply a large family of deciduous or evergreen shrubs or small trees that are cultivated primarily for their attractive blossoms.

They grow in a bush form or as a small tree. They grow anywhere from 3.9 inches to 98 feet in height, it all depends on the variety.

Rhododendron colours

The colours of the flowers can be pastel, white, orange, golden, purple, red or pink, and most types produce fragrant flowers.

The fruit of Rhododendron is dry capsule, and the ripe fruit will usually split lengthways to release their seeds.

The pollen and nectar that is produced by some of the species contain a toxic substance which is called grayanotoxin and this can be poisonous to animals and humans. Horses are specifically more sensitive to this type of toxicity.

To identify intoxication, you should look out for irregular heartbeat, abdominal pain, involuntary muscle contractions and coma which can ultimately lead to death.

Honey is produced from some of these plants, and they have hallucinogenic and laxative effects.

What type of soil do Rhododendrons like?

rhododendron garden spring-blossom

Rhododendrons grow best in soils with a pH of 4.5-6.0, and they don’t grow very well in soil that have appreciable levels of calcium.

You should undertake a soil test to determine the pH scale of the soil and so you’re able to make any amendment.

Agriculture sulphur is preferred over aluminium sulphate as the aluminium can be harmful.

It is best planted in groupings in prepared beds instead of individual planting holes. If they are planted in moisture-retaining but well-draining, loamy fertile soil, they will be easier to care for. It is recommended to have a 50 percent ratio of organic matter as a soil amendment as it provides drainage and aeration.

When do I plant Rhododendron?

The best time to plant Rhododendron is in spring as there is little danger of frost. Ensure that your soil is properly prepared, as waterlogged and soggy roots can cause the plant to struggle.

You will most likely purchase a containerised plant or a balled and burlap specimen. If you have it in a root ball, then this should be soaked prior to planting. For proper rhododendron care, moisture is key.

Place your plant in a bucket or tub for brief soaking and until air bubbles have disappeared. You should plant the bush so that its crown is at the same level as the pot.

Plant your Rhododendron 2 to 6 feet apart (depending on estimated mature size) and dig a hole as deep as the root ball and 2 times as wide.

Caring for your Rhododendron

Once you’ve planted your Rhododendron, you should water it thoroughly and cover it with organic mulch which will then break down to supply the right nutrients as it decomposes.

To inhibit fungi that causes root rot, you should apply a pine bark that covers 2inches. Ensure not to use peat moss as mulch, it is too difficult to rewet after it has dried out.

You should fertilise yearly, during Autumn or early Spring. Use fertiliser for acid-loving plants, such as organic cottonseed meal.

Too much water creates problems for the growing plant, so ensuring you have the right amount is vital in the care you give. If you notice leaves are curling and twisting, this is an indication that water is immediately needed.

How do I make my soil better suited for Rhododendrons?

As previously mentioned, add compost or peat moss to make sure your soil has plenty of organic material. Apply mulch around the roots to keep them covered and consider using pine needles, maple leaves, or oak leaves, as they are more acidic than other types.

Size and Leaf Type

If you don’t do your research and homework about your chosen plant’s eventual size, it could end up disastrous. There are so many types of Rhododendron, ranging from a small plant to a massive tree.

They typically grow to around 10 feet tall, but they can range from 6 inches to almost 100 feet in height! – remember some varieties lose their leaves in autumn, while others will hold their leaves right through the year.

Where to place your Rhododendrons

rhododendron blossom

Ensure that you have a sheltered place but avoid deep shade beneath trees. Some will cope with full sun as long as your soil doesn’t dry out. Avoid frost pockets and sites exposed to early morning sun and this can damage the flower buds.


This incredible plant will forever give you something to admire. Even though it seems quite difficult to grow and care for, once it’s planted and established, you just have to ensure that you’re giving it enough water in times of hot weather or drought.