What would a garden be without its colorful blooming plants? It's not without reason that spring is the most beautiful season of all for many people. The colorful bloom of some shrubs lasts into the summer and even into the fall. For example, with the rhododendron, whose numerous varieties delight the gardener with magnificent flowers almost all year round. Outdoors, the flowering period is from January to August.
Flowering times of different rhododendron varieties
Early flowering varieties
- Rh. dauricum 'April Reign'
- Rh. impeditum 'Ronny'
- Rh. ponticum 'Filigree'
- Rh. calophytum 'Sarastro'
- Rh. Hybrid 'Kromlauer Parkperle'
- Rh. yakushimanum 'April Morning'
- Rh. Hybrid 'Friesiane'
- Rh. Hybrid 'Minas Snow'
- Rh. yakushimanum 'Wanna Bee'
- Rh. yakushimanum 'Sasonade'
- Rh. yakushimanum 'Priscilla'
April-mid-May
- ‘Andrea’
- ‘Bengal’
- , Baden-Baden‘
- ‘Hachmann’s Andrea’
- ‘Susan’
- ‘Princess Anne’
- ‘P. J. M. Elite’
- City of Essen‘
End of May - mid-June
- ‘Azurro’
- , Anastasia´
- , Blue Peter´
- , Berlin Love´
- , Caslap´
- , Ice Princess´
- , Busuki´
- , Germania´
- , Gold Bucket´
- , Hachmann’s Charmant´
- , Gomer Waterer´
- , Kermesina Rosé´
- , Marcel Ménard´
- , Kocardia´
- , Rasputin´
- , Nefertiti´
- , Scintillation´
- , Satschiko´
- , City of Westerstede´
Varieties blooming in July
- Rh. viscosum varieties
- Wild species for example Rh. camtschaticum
Late flowering varieties in early autumn
- ‘Autumn Joy’
- ‘Cunningham`s White’
- Rh. yakushimanum 'Koichiro Wada'
- ‘Autumn Magic’
- ‘Autumn Greetings’
- ‘Vintage’
Note on flowering time
Of course, the exact time the flowers open is subject to natural influences such as weather conditions and temperature. The flowering times of the different varieties can therefore overlap. From the trade names of the late-flowering plants it can be seen that in most cases they are cultivars or hybrids. The latter are hybrids of different Rhododendron species. The shrub's natural flowering time is spring. Varieties that deviate from this period were specifically used to delight with their foliage throughout the entire garden season.
What's interesting is that the actual bud formation begins in August after the flowering period. The cultivated species are therefore incorrectly referred to as late-flowering. In reality, these are fresh flowers. Specimens that open their buds in the spring of the following year are the actual latecomers.
Tip:
There are plants that you just never get tired of looking at. If you want to enjoy the rose-like flowers of the rhododendron all year round, it is best to plant different varieties in your garden. As soon as one bush has finished blooming, the next one is already opening its buds. In this way, the gardener not only ensures a variety of colors, but also durability.
What to do if the flowers fail?
Even if the exact time of bud development cannot be precisely predicted, a long delay indicates inconsistencies. In some cases, flowers do not form at all. The following reasons could be possible:
Care errors
If the rhododendron does not bloom at the typical time, the first thing the gardener should consider is a management error.
These include:
Location
Especially if the rhododendron is too dark, it needs more energy to carry out photosynthesis with the few rays of sunlight. As a result, it lacks the strength to develop lush flowers.
Substrate
Under no circumstances should the rhododendron be planted in soil that is too calcareous. For he althy growth and the associated flower formation, the shrub needs a slightly acidic pH value (4.0-5.0). This is best achieved with special rhododendron soil from specialist retailers. Alternatively, a mixture of peat and sand is recommended.
Watering behavior
It is equally important that the root ball is always kept moist. However, waterlogging must not form as this leads to root rot.
Fertilizer application
A little fertilizer can certainly lead to increased flower production, especially if it contains plenty of phosphorus. Too much of a good thing has a negative effect. The rhododendron cannot tolerate additional nitrogen.
pruning
Due to the previously mentioned flowering in the previous year, the rhododendron must not be cut in spring.
Tip:
The crown should be thinned regularly. Among other things, this increases the light supply.
Seed rearing
Anyone who has proudly grown their own rhododendron from seeds will be disappointed a few months later. Only growing from cuttings or grafting produces flowers relatively quickly. Seedlings take many years before they form the first buds.
Frozen Buds
If the winter is particularly mild, the rhododendron opens its buds prematurely. If it is then surprised by frost again, the young flowers die and do not grow again until spring.
Room Culture
Container plants that are kept indoors usually only last one season. Furthermore, this attitude is only possible with varieties that bloom from January to April. A cool location and regular watering are essential for indoor culture. If you want to enjoy the flowers the following year, you should put the rhododendron outside after the night frosts have subsided.
