May 18 2013 Latest news:
Martyn Davey, Head of Horticulture and Design, Easton College
Wednesday, June 13, 2012
Question: I hope you will be able to tell me how my camellia has been able to produce pure white flowers this year. It started life as a small pot plant, almost 20 years ago, and producing pink flowers. Now in our garden, it has produced this colour ever since – until this year when it produced about 20 pure white flowers out of a total of about 200-300 blooms. The only treatment it has had is an annual dose of sequestrene. (D Hewitt, Dereham)
Camellias are one of the most popular winter- and spring-flowering shrubs, providing a vivid splash of colour when little else is in bloom. Although they need acid soil, they are easy to grow in containers of ericaceous (acidic) potting compost. Camellias are woodland plants that grow best in shelter and light shade, although with careful watering they can be grown in sunny positions. They prefer free-draining conditions, with plenty of organic matter incorporated into the soil. If your soil isn’t acid then consider growing your camellia in a container. Tap water often contains too much calcium for them, so rain water is ideal. If rain water runs out, tap water is satisfactory for a month or two in summer.
Feed camellias with acidic fertilisers, such as Chempak Ericaceous, Miracid, sulphate of ammonia or sulphate of potash. Controlled release fertiliser pellets are available from Miracid and Phostrogen to mix into the potting compost of container-grown plants, avoiding the need for further feeding until the following season.
You can also use organic fertilisers, including fish, blood and bone and seaweed products.
Like other early-flowering shrubs, camellias form flower buds in late summer and autumn, especially on new growth. Pruning at this time could remove potential flowering growth. Therefore pruning is best done in spring, immediately after flowering.
Where an overgrown camellia needs to be reduced or renovated, hard pruning is usually safe and reliable.
Some camellias have this peculiar habit of producing different coloured flowers on different parts of the same plant. This is known as ‘sporting’ and is not that unusual although it can come as a surprise. Sporting is the way in which a plant reveals part of its genetic makeup or parentage. The most obvious sporting occurs where red and white camellias have been crossed to produce a mottled or flecked double flowered hybrid. Such hybrids often also exhibit single white and or single red flowers as well. Camellia ‘Tricolor’ and Camellia ‘Adelina Patti’ are good examples of this trait. Your pink camellia over time is reverting back to its original parentage and may well end up as a white flowered camellia.
Camellias are occasionally subject to problems. Failure to flower and loss of flower buds are common problems, but can be avoided by providing good growing conditions. Water during dry spells in late summer, mulch with an 8-10cm layer of chipped bark or leaf mould in late winter or early spring to conserve water around the rootsm and move container-grown camellias out from under the eaves of the house in late summer or autumn so that they catch the rainfall.
Protect tender cultivars with a double layer of horticultural fleece in winter, as low temperatures can lead to bud drop.
As with all evergreen shrubs, leaves are replaced every few years; each year a proportion of the foliage (mainly older leaves near the base and within the plant) are shed, usually in spring and summer. This is normal and not a cause for concern.
Clematis armandii is a great favourite of mine but, it has its drawbacks. First of all, it is not the hardiest member of its tribe, and being evergreen, once its foliage becomes frost damaged this becomes a permanent feature.