Rhododendron - planting and care

Scientific name (Latin): Rhododendron,

Family: Heath family (Ericaceae)

Cultivating your own rhododendron is an investment that will pay off for many years to come. In addition to blooming early, smelling good, and being relatively easy to care for, they also provide evergreen foliage for your garden. With the right conditions and a little care, you have all the opportunities to bring out beautiful, healthy rhododendrons that thrive in your garden.

The genus rhododendron comprises over 900 different garden plants, all with their own unique colors, shapes, and blooming times, although most bloom early in the spring. In recent years, interest in this beautiful plant has increased, and even more hybrids are entering the Norwegian market. The name comes from the Greek rhodo which means rose or tree, combined with dendron which means tree. Explore our selection of rhododendrons.

First, choose where in the garden you plan to plant your rhododendron, and choose the location or species. It is advisable to plant several bushes together, as this is a social plant that thrives in company.

Location and growing site
Rhododendron prefers a quiet and protected growing site, preferably in partial shade, but they can also thrive in a more sunny location. If you choose such a location, make sure to water extra on hot days.

Soil for rhododendron
The soil where the bush is to be planted should be acidic, with a pH value of about 4.5 – 5.5 for the rhododendron to thrive. Also, make sure it is low in lime, porous, and well-drained. Use rhododendron soil when planting. You can also mix in some undisturbed peat, compost from oak or beech leaves, and/or bark to further improve the quality. You can even mix in some gravel.

Planting rhododendron
Rhododendron has a shallow root system and should not be planted too deep. For larger plants, prepare a depth of about 40 cm for the bush and around 70 cm in diameter. Let the top of the root ball be just a few centimeters below the soil surface. Water generously during planting and throughout the first season.

Cover the soil to protect the bush
After planting, it is good to cover the soil with beech and oak leaves, bark pieces, or other slowly decomposing plant materials with a low pH value – to protect your bush.

Watering
Rhododendrons need a lot of water, but they cannot tolerate constant moisture. Ensure good drainage. In the fall, before the frost arrives, it is wise to water generously, even if it has rained a lot recently. Rhododendrons store and use water reserves throughout the winter, as they evaporate a good amount of liquid through their leaves year-round.

Fertilize your rhododendron
Rhododendrons grow slowly and therefore require limited nutrients. In the spring, you can fertilize after the shrub has bloomed, using a special rhododendron fertilizer. If the soil has settled, you can top up with more rhododendron soil.

Protect from the spring sun
If the sun starts shining in the spring but the frost has not thawed, it is wise to protect the shrub with burlap sacks. Otherwise, the shrub may risk getting damage that is difficult to overcome.

Remove wilted flowers
Keep your shrub fresh and tidy by regularly removing wilted flowers. This also facilitates the growth of new leaves and buds.

How to prune your rhododendron
Pruning is not necessary, but if the shrub becomes bare and unattractive, it can be rejuvenated by pruning. Either the whole plant at once or parts of the plant over a few years. Remove all damaged and dead branches you find in the shrub, and prune the shrub if you think it has become too large or heavy. Aim for pruning down to about 10-15 cm above ground level, preferably in the spring

The first time the name is found in history is around 100 AD, when it appears in the work of the physician and botanist Dioscorides. However, at that time it was a completely different plant that went by that name, namely Nerium Oleander. It was Linnaeus who later took the name and instead passed it on to the rhododendron genus. Linnaeus was also the first to identify some rhododendron species, including the Swedish Azalea Lapponicum found in Jämtland in Härjedalen.

It is also possible to date it back to the time of Alexander the Great, where descriptions of rhododendron, specifically the species Azalea Luteum, have been found. It is said that parts of Alexander's army may have eaten luteum honey and become ill from it. But even though the plant is not mentioned in history prior to this, fossils dating back 50 million years suggest that this plant has existed for at least 200 million years.

The flowers are either white, yellow, red, green, or blue. Many species are grown as ornamental plants. There are both giant plants with 1-meter-long leaves and miniatures with 8–10 mm long leaves. It is said to have existed for nearly 200 million years. An easy-to-care-for bush that suits most gardens.

Check out our selection of rhododendrons

Read also:
Azalea - facts and advice on care

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