Getting it to bloom
Why won't my Rhododendron 'Fastuosum Flore Pleno' bloom? (and how to make it flower)
Also called Double-flowered Rhododendron, Fastuosum Rhododendron (Rhododendron 'Fastuosum Flore Pleno').
More about rhododendron 'fastuosum flore pleno'
About Rhododendron 'Fastuosum Flore Pleno'
Rhododendron 'Fastuosum Flore Pleno' · also called Double-flowered Rhododendron, Fastuosum Rhododendron · flowering
Rhododendron 'Fastuosum Flore Pleno' is a vigorous, hardy evergreen hybrid notable for its semi-double mauve-purple flowers with a yellow-green blotch, produced in late spring. An old cultivar dating to the 1840s, it is exceptionally wind-tolerant. All parts are toxic to pets due to grayanotoxins.
Plant type: flowering
Watch for — Bud blast: Brown, shrivelled buds that fail to open are caused by leafhopper-spread fungus; control leafhoppers and remove affected buds.
The reasons rhododendron 'fastuosum flore pleno' isn't blooming
Almost every non-blooming rhododendron 'fastuosum flore pleno' traces back to one of these, roughly in order of how common they are:
- Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
- Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
- The plant has not been deadheaded, so it stops flowering once it sets seed.
- Irregular watering — drought or waterlogging at the budding stage makes buds abort.
- It is still too young or was checked by a transplant and is rebuilding before flowering.
Feeding rhododendron 'fastuosum flore pleno' a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.
The fix — how to get rhododendron 'fastuosum flore pleno' to flower
- Maximise sun. Give rhododendron 'fastuosum flore pleno' the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
- Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
- Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
- Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.
Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for rhododendron 'fastuosum flore pleno' and get the feeding right with the rhododendron 'fastuosum flore pleno' fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.
Bloom season and what to expect
Rhododendron 'Fastuosum Flore Pleno' flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.
Post-bloom care so it flowers again
Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.
For everything else this plant needs day to day, see the full rhododendron 'fastuosum flore pleno' care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.
Rhododendron 'Fastuosum Flore Pleno' blooming — frequently asked questions
Why won't my rhododendron 'fastuosum flore pleno' flower?
Rhododendron 'Fastuosum Flore Pleno' blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
How do I make rhododendron 'fastuosum flore pleno' bloom?
Give rhododendron 'fastuosum flore pleno' the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
When does rhododendron 'fastuosum flore pleno' normally bloom?
Rhododendron 'Fastuosum Flore Pleno' flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.
What should I do with rhododendron 'fastuosum flore pleno' after it flowers?
Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.
What is the single biggest mistake stopping rhododendron 'fastuosum flore pleno' flowering?
Feeding rhododendron 'fastuosum flore pleno' a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.
Keep reading
- Rhododendron 'Fastuosum Flore Pleno' care — the full brief (light, water, humidity, problems, pet safety)
- Rhododendron 'Fastuosum Flore Pleno' light needs — usually the first thing to fix for flowers
- Rhododendron 'Fastuosum Flore Pleno' fertilising — the right feed for buds, not just leaves
- Should I water my plant? The simple check
- Why is my plant wilting? Wet vs dry
- Underwatered plant — signs and rehydration
- Why won't my peace lily bloom?
- Why won't my jade plant bloom?
- Why won't my tomato bloom?
- All 4831 bloom guides in the Growli library