Plantswoman FIONA EDMOND, who owns the award-winning Green Island Gardens in Ardleigh, shares her gardening tips. Today she focuses on Camellias...

I am frequently asked how I get my Camellias to flower so well? The answer is that I really do nothing to encourage them, but the secret I believe is giving them conditions that they like. Generally Camellias thrive in semi or dappled shade, and well-drained acidic soil (pH 6.0 to 6.5).

Planted in deep shade they will not flower at all. They also require ample moisture during the growing season and in particular from July to August when the buds are forming for the next year.

Lack of water at this time will cause premature bud drop the following season. Ideally planted in Autumn they should be protected from rabbits and watered for the first two seasons after which they are surprisingly undemanding and able to fend for themselves.

Here at Green Island I have some Camellias which were planted before I took over the garden and are placed in hot dry sunny spots against a south facing wall.

I would never have dreamed of planting in such conditions however they are thriving and defy all the conventional rules of growing Camellias. Camellia williamsii ‘Donation’ in particular is a very free flowering variety and doesn’t mind being pruned back hard every year after flowering to keep its size in check.

Avoiding an east facing spot where early morning sun will cause frosted buds to thaw quickly and blooms to turn brown and mushy is advisable, and in general a sheltered spot will be appreciated. If growing camellias in pots then it is best to water them regularly with rainwater as tap water is generally alkaline.

Echo: gardening

When Camellias were introduced to Britain they were often grown in glasshouses and conservatories as it was believed they would not be fully hardy.

However generally spring flowering varieties namely C. Japonica and C. williamsi hybrids are hardy to -10C with the latter being more able to withstand wind and frost, flowering over a longer period than C. japonica from March to late April, and having the added advantage that they shed their blooms as they fade unlike the japonicas which hold onto theirs, spoiling the appearance of the later blooms.

C. japonica varieties with their single flush of flowers in late March are best suited to the mild damp south west of the country. C. sasanquas, (the autumn flowering camellias) are slightly more tender, surviving in theory only down to -5C, however I have many sasanquas that have survived temperatures down to -15 on successive winters. They flower over a long period and have sweetly scented flowers. There are certain varieties which reliably seem to flower profusely, and the ones I would recommend are

C.x williamsi ‘Anticipation’- peony form, double deep rose pink flowers. Ideal for training on a wall or fence

C.x williamsi ‘E G Waterhouse’ – strong upright growing form with formal double

Camellia sasanqua ‘Hugh Evans’- Sweetly scented strong pink single flowers with

prominent yellow stamens from October-December. C sasanqua ‘Hugh Evans’

Lack of flowers and yellowing of the leaves seem to be the most common ailments, both of which can be avoided by planting Camellias in a spot where they will be happy.

The other problem that occurs is a black sooty mould appearing over the leaves. It is normally caused by scale insects or less frequently aphids. These secrete a sweet sticky substance as they feed on the leaves. This attracts fungi which cause the black sooty material. This is unsightly but rarely causes much damage.

The cure, if you have only a small camellia, is to wash it off by hand using slightly soapy water - a couple of drops of washing up liquid per pint of water. Larger plants can be sprayed with water which will wash off many of the aphids and some of the sooty mould. Alternatively a spray with a general insecticide will do the trick.

If your soil is heavy clay or alkaline chalk then best not to attempt to grow Camellias. Yellowing of the leaves is a sure sign that your Camellia is not happy. Lack of magnesium or iron as well as overwatering will cause the leaves to turn yellow.

Feeding with ericaceous feed every month during growing season may help but my feeling is that if the conditions do not suit Camellias then they would look out of place anyway.

When teaching my design students I point out that you would not attempt to grow Sempervivums in tropical jungle conditions nor would you try growing tree ferns on an exposed hilltop. Either would look ridiculous. Camellias are woodland plants and look happiest in those conditions.

There are over 150 varieties of Camellia growing at Green Island Gardens and many can be purchased in the nursery. For further information visit www.greenislandgardens.co.uk