In some gardens and parks there are he althy, lush rhododendrons. It's so green. They grow and thrive but do not bloom. Even for gardeners and botanists, it is not always easy to find the cause. Some of the most common reasons why rhododendrons don't produce flowers:
Why isn't my rhododendron blooming?
If a rhododendron does not bloom, it may be due to lack of light, incorrect fertilization, incorrect pruning, pests, diseases, seedling propagation or prematurely opened buds. To remedy this, the location, fertilization and care should be adjusted.
- Lack of light
- Incorrect fertilization
- Incorrect pruning
- Pests or diseases
- Seedling propagated plants
- Buds open prematurely
Flowering strike due to lack of light
Even rhododendrons go on flowering strike due to lack of light. When rhododendrons are completely in the shade, they use all their energy to create enough leaf area to take advantage of the few rays of sunlight. In doing so, they reduce the formation of flowers.
What to do? In autumn, move the plant to a sunnier location or ensure more light by cutting back and thinning out the treetop.
Incorrect fertilization
Too much good food not only makes us humans, but also the rhododendron fat and lazy to bloom. Overfertilization with nitrogen and phosphorus reduces the abundance of flowers. Both active ingredients activate growth and leaf formation while phosphorus contributes to flower formation.
What to do? If possible, use pure nitrogen fertilizer in organic form (cattle manure or horn shavings) to avoid one-sided fertilization. Match nutrient doses to the soil.
Incorrect pruning
Rhododendrons form their flower buds the previous year. If you cut them back before they bloom, you will miss out on the splendor of color for a season. You can only cut back late-flowering rhododendron varieties like Cunninghams White in spring.
Pests or diseases
An infestation of flower buds by rhododendron leafhoppers in May can destroy the flowers. What to do? Fight insects with insecticides until the end of May, remove all infected flowers early and dispose of them with household waste.
Seedling-propagated Rhododendron
Propagate rhododendrons from seedlings means waiting years until the first blooms. Vegetatively propagated cuttings or grafts bloom after just one or two. What to do? When buying rhododendrons, pay attention to refined specimens!
Buds open prematurely
During a warm weather period in winter, the buds open prematurely and freeze before they bloom. In any case, the following normal flower is lost. Diseases can also occur before the buds open.
Tips & Tricks
When you replant or move a rhododendron, it usually doesn't form any buds. Then it doesn't bloom the following year. It can also happen that it occasionally stops flowering when it is young or what are supposed to be flower buds are actually larger leaf buds.
