The rhododendron plant genus is particularly rich in species and diverse. We show you the most popular and beautiful rhododendron species and varieties.
Every rhododendron lover is probably aware of the enormous variety of rhododendrons (Rhododendron). The genus belongs to the heather family (Ericaceae) and includes well over 1,000 species worldwide with countless different varieties. To help you keep track, we have compiled the most beautiful rhododendron species and varieties for you below. Before that, however, we would like to share some exciting insights about the rhododendron and its numerous species with you.
Rhododendron: origin and characteristics
The geographical distribution of the rhododendron is distributed over large parts of the world. Small dwarf species are found in sub-polar climate zones, tree-sized plants are more typically found in tropical and sub-tropical areas. But not all rhododendron species are suitable for cultivating in our home garden. Most of the cultivated forms of rhododendrons that are common today come from Southeast Asia. In nature, they mainly occur on moist, humus-rich soils and prefer slightly acidic conditions.
But there are also native rhododendrons in Germany. The rust-leaved alpine rose (Rhododendron ferrugineum) and the ciliated alpine rose (Rhododendron hirsutum), for example, can be admired in the southern Alps. In the past, a distinction was made between the genus of rhododendrons and azaleas. In the meantime, however, the azaleas are also counted among the rhododendrons, as there are great similarities between the two. The most popular group of rhododendron varieties is that of the large-flowered hybrids, which can reach several meters in height and are often planted as privacy screens. Among the azaleas, the Knap Hill hybrids are the favourites, closely followed by the Japanese azaleas. There are also the non-hardy indoor azaleas (Rhododendron simsii), which are very attractive indoor plants with their flowering in winter.
With so many species and varieties, it's difficult to get an overviewto keep. We will give you a quick overview of the most important rhododendron species.
Rhododendron species: The most beautiful species
The taxonomic classification of rhododendrons is relatively difficult. On the one hand, there are an incredible number of species worldwide that have never been named according to a uniform system. On the other hand, new breeds constantly ensure a never-ending stream of great new varieties. The most common method for the taxonomic classification of rhododendrons is currently Chamberlain's. We present a brief overview of some well-known species:
Japanese Azaleas (Rhododendron molle subspez. japanicum): Also Azalea mollis or garden azalea called. The group includes various species hybrids with similar characteristics. Most of them are R. obtusum hybrids.
This evergreen group loses smaller to larger parts of its foliage in winter depending on the temperature and usually has a beautiful red autumn coloration. In summer, the leaves are green on top and blue on the bottom. The compact growing azaleas are about one meter high and are therefore particularly suitable for rock gardens, as grave plants or container plants. From May to June, the plants impress with a veritable sea of small, pink flowers. Sunny to partially shaded locations are tolerated. The following varieties belong to the species of Japanese azalea:
Alexander: Large, orange-red flowers; Growth height up to 55 cm
Betty Muir: Medium, light pink flowers; Growth height up to 40 cm
Cherie: Double, salmon-colored flowers with a red eye; Growth height up to 45 cm
Chippewa: Large, light pink flowers with a red eye; Growth height up to 45 cm
Diamond Red: Large, ruby-red flowers that lighten as they fade; Growth height up to 30 cm
Elsie Lee: Double, pink flowers with red markings and wavy petal edges; Growth height up to 90 cm
Estrella: Red flowers; Growth height up to 35 cm
Azalea obt. Fairy Pillow ®-EU-S-: Large, white flowers; Growth height up to 30 cm
Kermesina: Light red to ruby pink flowers; Growth height up to 70 cm
Königsstein: Large, violet flowers; growth height up to 55 cm,
Labe: Large pink flowers with a brown center; Growth height up to 40 cm
Ledikanense: pink flowers with red markings; Growth height up to 90 cm
Madame van Hecke: pink flowers; Growth height up to 70 cm
obt. Peppina ®: Large, pink-purple flowers with a redDrawing; Growth height up to 30 cm
obt. Purple Cushion -S-: Ruby red flowers; Growth height up to 40 cm
Rococo: Double pink flowers; Growth height up to 40 cm
Snowglow: white flowers with yellow-green markings; Growth height up to 100 cm
Satschiko/Geisha Orange: Large, orange flowers; Growth height up to 45 cm
Azalea Satsuki (R. indicum): The evergreen species has small leaves and a dense, compact habit. This makes it ideal for topiary and for bonsai training. They are hardy and bloom from early May to early June, with over 1000 different varieties offering an impressive range of colours.
Hidoshi: Pink flowers with white-pink eye
Kegon: pink flowers with narrow petals
Kiri-no-hikari: White-Purple Patterned Flowers
Korin: Pink flowers with a slightly darker centre
Reiko: Creamy white flowers with red speckles
Shisui: Pink Flowers
Wakaebisu: Salmon colored flowers with pink speckles
Yuki: White flowers with pink markings and speckles
Rhododendron wardii: The yellow-flowering, evergreen wild form comes from China and is sufficiently hardy for us. The mainly yellow to orange flowering hybrids of R. wardii grow up to three meters high.
Brasilia: pink/yellow flowers in May to June; growth height up to 250 cm; INKARHO
Christian: Golden yellow flowers with a warm touch of pink in May to June; Growth height up to 100 cm
Ehrengold: pink-yellow buds and light yellow flowers in May to June; Growth height up to 250 cm
Golden bouquet: Cream-yellow flowers with red spots in May; Growth height up to 150 cm
Sprinkles of Gold: Yellow flowers with brown spot pattern in May; Growth height up to 80 cm
Graf Lennart: Bright light yellow flowers with red spots in May, growth height up to 110 cm; INKARHO
Schneespiegel: White flowers with a wine-red center in May; Growth height up to 150 cm
Dwarf Rhododendron (R. forrestii earlier repens): Draw this species as well as its hybrids characterized by a low, squat growth that rarely reaches more than a meter in height. Therefore, this species is ideal for surface greening and as a ground cover. Some of the mostly red flowers appear as early as April. These are evergreen rhododendronsrelatively good to good hardy.
Evening glow: growth height up to 150 cm; Flowering: Late April to May in dark scarlet with yellow-green buds
Baden-Baden: growth height up to 90 cm; Flowering time: May in scarlet with yellow-green buds
Bengal: growth height up to 60 cm; Flowering time: May in bright red
Red Carpet: growth height up to 90 cm; Flowering period: end of April to May in fiery red with brown-red buds
Scarlet Wonder: growth height up to 60 cm; Flowering time: early to mid-May in bright red with brown-red buds
Topsi: growth height up to 20 cm, flowers: April to May in pink with a wavy edge
Red rhododendron (R. russatum): Native to central China, the species is evergreen with small, dark green leaves and grows in pairs Meter high. The mostly blue to violet, rarely pink to white flowers appear from mid-April or May to the end of May. Unlike most rhododendron species, prefers R. russatum sunny locations. The species is hardy but loses some of its foliage. Numerous small-flowered hybrids emerged from it.
Azure Cloud: Blue-purple flowers; Growth height up to 90 cm
Compactum: blue-purple flowers; Growth height up to 40 cm
Gentian: Dark purple-blue flowers; Growth height up to 80 cm
Gletschernacht: Blue-violet flowers; Growth height up to 120 cm
Lauretta: purple-blue flowers; Growth height up to 90 cm
Purple Pillow: purple flowers; Growth height up to 60 cm
Rhododendron williamsianum : Also called bell rhododendron. The mostly pink flowers hang down slightly due to their long flower stalks. The leaves are also very special with their almost round shape and the reddish leaf shoots. The shrub, which grows to a height of around 60 cm, is also hardy.
August Lamken: Pink flowers with dark pink spots in May; Growth height up to 140 cm
Garden Director Glocker: reddish pink flowers with red buds in May; Growth height up to 110 cm
Garden Director Rieger: Cream-white flowers with red-brown spots in May; Growth height up to 160 cm
Lisbon: Pink-red flowers with a light center in May; growth height up to 100 cm; INKARHO
Vater Böhlje: Light lilac flowers in May; Growth height up to 80 cm
Small-leaved/Dwarf Rhododendron (R. impeditum): This evergreen,hardy species not only has small leaves, with a final height of about 40 cm it is also one of the lowest rhododendron species. The growth is bushy and wide. In May, the dark green leaves with a spicy scent almost completely disappear behind a blue to violet coat of flowers. The small-leaved rhododendron thrives in partially shaded and even shaded locations. This makes it ideal for planting under taller shrubs and trees.
Bluebeard: Light blue flowers; Growth height up to 80 cm
Blumiria: purple flowers; Growth height up to 50 cm
Moerheimii: Pastel lilac flowers that appear as early as the end of April; Growth height up to 40 cm
Ramapo: pink-purple flowers; Growth height up to 80 cm
Violetta: lilac-violet to blue flowers; Growth height up to 80 cm
Dauric Rhododendron (R. dauricum): This early spring rhododendron starts with us in mild weather as early as November beginning to bloom. The whole blooming splendor appears from February and March until April. The flower color ranges from soft pink to violet.
April Reign: Pale pink flowers in April; Growth height up to 100 cm
April Rose: Large bright pink flowers in March and April; Growth height up to 140 cm
Mid-Winter: Violet to pink flowers; Growth height up to 1.5 meters
Praecox: lilac flowers from late March to mid-April; Growth height up to 60 cm
Staccato: semi-double, pink flowers with a slight shade of red; petals slightly ruffled; Growth height up to 130 cm
Tree Rhododendron (R. arboreum): The giant among the rhododendrons grows in the wild as a tree of up to 30 m Height. The young shoots and the undersides of the leaves of this species have woolly hairs. In spring, inflorescences are formed with up to 20 bell-shaped flowers in red to purple. In the native regions of the tree rhododendron, various mountain regions of Asia, the nectar of these flowers is used in cooking. In Nepal it is even the national flower. The evergreen tree loses some of its leaves in severe frost and is only conditionally hardy in our country. Only the subspecies R. arboreumspp. Delavayi is considered hardy in mild regions in a sheltered spot. The hybrid varieties of this species do not grow as tall as the wild form, but produce beautifully colorful flowers.
Bibiani: Bright red flowers in September; growth heightup to 3 m
Blue Baron: Blue-purple flowers with golden-yellow markings that become lighter on the inside; Growth height up to 120 cm
Cornubia: fiery red flowers from the end of February/beginning of March
Ebony: Pink flowers with an orange-red centre
Dwarf Alpine Rose (Rhododendron keleticum): The dwarf alpine rose grows dense and compact, reaching a height of just 25 cm . It is therefore wonderfully suited for surface planting. The flowers appear from the end of May to the beginning of June in a strong purplish violet with red markings. The petals are conspicuously wavy and frayed at the edge. In winter, the plants lose all their foliage. But they are completely hardy.
Robert Seleger: Carmine red to light pink flowers; Growth height up to 30 cm
Indoor azaleas (Rhododendron simsii): The indoor azaleas have beautiful large flowers in more or less strong shades of pink. In addition, they rarely grow higher than 50 cm. This coupled with the frost sensitivity of the Taiwanese exotics makes them the ideal houseplant.
Fortunes Rhododendron (R. fortunei): This wild species is considered one of the most beautiful and at the same time exudes a wonderfully sweet scent when the delicate white-pink flowers appear from mid-May to mid-June. The bushy to tree-like plants are adorned all year round with long, oval leaves that slope slightly downwards. The buds are attractively scaled. The species, which originates from Asia, is only conditionally hardy here.
Rhododendron subgenus Hymenanthes : Tree-like varieties up to 25 m tall; rather unpopular in German gardens; partly hardy to -15 °C; flowering between January and May; mostly pink to strong red flowers.
Section Rhododendron Pentanthera : Growth habit varies between tree and shrub (3 to 5 m in height); some varieties hardy to -18 °C; flowering time April to May; mostly single white flowers.
After this detailed list of the different rhododendron species and their varieties, you will find the 50 most beautiful rhododendron varieties in our special article.
Deciduous Rhododendrons: Our Top 20
If you are also interested in deciduous rhododendrons, then we have compiled a few popular and very ornamental deciduous varieties for you below.
Rusty Dane (Rhododendron bureav):Danish variety; rust-colored underside of leaves, slightly rust-colored, shiny upper side of leaves; compact growth
Vintage (Rhododendron smirnowii): Russian variety; double flowering period (pre-flowering in autumn, main flowering in spring); slightly felty growth; long, slender leaves; light beige
Goldflicker (Large-flowered hybrid): Flowers in June in lilac-pink with yellow-brown markings; growth height up to 140 cm; the leaves are green with a yellow center
Gold Leaf (Large-flowered Hybrid): Blooms in June in lilac-pink with a brown-yellow eye; growth height up to 140 cm; the leaves are green with yellow markings
Carolina Spring (Large-flowered Hybrid): Purple-pink flowers; growth height up to 140 cm; the
Graziella ( ponticum): Large, pink flowers with a velvety red center; from mid-May to early June; very narrow decorative foliage; Growth height up to 110 cm
You can find a detailed overview of deciduous rhododendron varieties here in our special article.
Tip: Once the right rhododendron variety has been found, it should be properly cared for and supplied with nutrients. A primarily organic organic fertilizer such as our Plantura organic hydrangea fertilizer with a long-term effect and an extra portion of iron is ideal for this.
INKARHO: Lime-tolerant rhododendrons for every soil
The word "INKARHO" has its origins in the "interest community of lime-tolerant RHOdodendrons". INKAHRO GmbH is an association of several tree nurseries, some of which have been growing lime-tolerant rhododendrons for several decades. Because rhododendrons are usually so-called ericaceous plants and need an acidic environment in order to be able to grow. The so-called INKARHO varieties such as Bloombux or other varieties mentioned above are specially refined rhododendrons. Tried-and-tested varieties, which cannot cope with alkaline soils, become more tolerant of calcareous soils by placing them on the INKARHO rootstock. In addition, a much more pronounced root growth can be seen in most grafts.
Rhododendron 'Bloombux': R. micranthum hybrids; very flowering and easy-care variety; is traded as a boxwood alternative; flowering time in April/May; delicate pink flowers; very strong and juicy leaves, especially in spring; evergreen
A detailed oneArticles about the Rhododendron 'Bloombux' can be found here.
Note: It is still advisable to mix in some peat or special rhododendron soil when planting, so that the soil is slightly acidified. In addition, soil life is promoted and the soil is more permeable thanks to the improved grain size spectrum.
Once you've decided on one of these beautiful varieties, it's time to plant the rhododendron. Check out this article for expert tips.