Q: My camellia, which is growing in a pot, has started dropping both its leaves and flower buds, and now looks pretty miserable. I’ve always made sure to keep it well watered but at this stage I’m beginning to wonder if it would be happier in the ground. Any tips on what I’m doing wrong? Helen McCarthy, Dublin
A: Camellias are very popular as container-grown plants for good reason, providing a great display of glossy, evergreen foliage and lots of dramatically beautiful, sometimes scented flowers which typically appear between late winter and late spring. But they do require consistent care and attention if they’re to flourish.
Natives of southeast Asia, these woody plants need a sheltered, mild garden, a humus-rich, moist but free-draining acidic soil or ericaceous compost, and a position in light shade with protection from frost and wind. In particular, camellias hate growing in an exposed, east-facing spot where they are vulnerable to damage from winter frosts and searing icy winds, which can cause both the leaves and buds to drop as a result of plant stress.
If this is the case with your plant, then moving it to a sheltered spot in dappled shade will help it to slowly recover, although it will be next year before you see the full benefits.
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But bear in mind that even in milder Irish gardens, pot-grown specimens are still more vulnerable to damage to their root systems during cold winter weather, which is why it’s generally recommended that you swaddle both the container and the lower half of the plant in a couple of layers of horticultural fleece when this is forecast. In exceptionally cold winter weather such as that experienced recently, it’s best to move the entire plant temporarily under cover of a frost-free glasshouse, polytunnel, porch, conservatory or even just a garden shed until conditions improve.
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Erratic or insufficient watering (especially during summer when the flower buds are forming) can also cause leaves and buds to drop, but from what you’ve described the latter doesn’t seem to be the problem, unless perhaps your camellia has gradually grown too large for its pot. These hungry, thirsty shrubs need a generous-sized pot to accommodate their root systems and then need to be repotted every couple of years into a larger container using fresh ericaceous compost until they’ve reached optimal size.
From then on they should ideally be repotted every two to three years in late autumn using the same container and fresh ericaceous compost, gently trimming back the root-ball to check excessive growth. Scrupulous deadheading, a light pruning after flowering, plus top-dressing the root-ball every spring with a light mulch of leaf mould or home-made garden compost and a couple of handfuls of slow-release granular fertiliser (this should be suitable for ericaceous plants) will also help to keep your container-grown plant happy and floriferous.
Finally, it’s worth adding that some varieties are notably more resilient in the face of winter cold than others. Examples of the former include Camellia x williamsii “Debbie” (double, rose-pink flowers in late spring; Camellia x williamsii “Anticipation” (hot-pink double flowers from late winter/early spring); and Camellia reticulata “Black Lace” (dark-red double flowers, mid-spring).
