In my garden, I’ve often had plants that looked perfectly healthy but just wouldn’t bloom — or only produced a few sad flowers. Over time, I’ve learned that even the best care can’t help if certain basic things go wrong. That’s why I’d like to share with you the most common reasons I’ve discovered for poor blooming and what I do about them.
Contents
1. Too Shady a Location
A shady spot is the number one reason my plants sometimes bloom poorly. If I plant sun-loving plants like lavender or coneflowers in too much shade, they focus all their energy on growing leaves to catch the little sunlight they get — and forget about making flowers. I either move these plants to a sunnier spot in autumn or thin out tree branches to let in more light. Even my rhododendrons, which don’t like full sun, produce far fewer flowers if they’re in deep shade.
2. Incorrect Fertilization
I’ve learned the hard way that too much fertilizer can make plants lazy when it comes to blooming. If there’s too much nitrogen and not enough phosphorus, my plants just grow lush green leaves and hardly any flowers. Nitrogen mainly helps leaf growth, while phosphorus encourages blooming. So I try not to use too much nitrogen-rich fertilizer and prefer organic options like manure or horn shavings. For my potted and balcony plants, I always use a special bloom fertilizer with enough phosphorus. I also adapt how much I fertilize depending on my soil: Heavy clay soil needs less than sandy soil.
3. Incorrect Pruning
Many spring bloomers in my garden — like forsythia, viburnum, mock orange, or fruit trees — already form their flower buds the year before. If I prune them at the wrong time, I end up cutting off all the buds and miss out on flowers for a whole season. Only summer bloomers like hibiscus, panicle hydrangea, and butterfly bush can be pruned early in spring. Their flowers come a bit later but are even more impressive. One exception I watch out for is the bigleaf hydrangea: it sets its buds the year before too.
4. Seed-Grown Plants
I also know that plants grown from seeds often take years to flower, while plants from cuttings or grafted ones bloom much sooner. This is because seed-grown plants go through a full ‘youth’ stage first. I always check how a plant was propagated when buying it. Wisteria is a good example — seed-grown ones can take over ten years to bloom and never look as lush as grafted ones. So I avoid cheap wisteria offers, as they’re almost always seedlings.
5. Biennial Blooming (Alternation)
Some of my plants naturally follow a two-year rhythm: One year they bloom a lot, the next year hardly at all. This is called alternation and happens, for example, with some apples like ‘Red Boskoop’ and ornamentals like lilac. After a big bloom, the plant puts so much energy into seeds that it forgets to set new flower buds. To prevent this, I remove dead flowers before seeds form and thin out fruit early. This way, the plant puts its energy back into forming new flowers.
6. Pests or Diseases
My rhododendrons have sometimes been ruined by the rhododendron leafhopper in May. This pest lays eggs under the bud scales and spreads a fungus that dries out the buds. I control them with insecticides before the end of May and remove any affected buds early. I throw them in the trash or bury them in the compost.
7. Non-Flowering Varieties
Some plant varieties are simply not meant to flower — they were bred for beautiful leaves or special shapes instead. Examples in my garden include the globe locust (Robinia pseudoacacia ‘Umbraculifera’) and the globe catalpa (Catalpa bignonioides ‘Nana’).
8. Special Life Cycle
A few plants need special conditions to bloom. For example, my poinsettia is a short-day plant — it comes from the equator, where days and nights are about the same length. If it gets too much light indoors, it doesn’t bloom. From October, I cover it completely for twelve hours each day for four to six weeks. By Christmas, it’s full of blooms again.
My amaryllis (Hippeastrum) also needs special care. From early August to early November, it needs a rest period. I stop watering in August and wait for the leaves to yellow. Then I cut them off and store the bulb in a cool, dark place (15°C is ideal). At the start of November, I repot and water it — and by Christmas, it rewards me with beautiful flowers.
My Final Tip
I know it can be frustrating when healthy plants refuse to bloom. But in my experience, there’s almost always a reason — and often an easy fix once I understand what my plants need. I hope my tips help you enjoy your garden in full bloom!
