Garden Centre

Friday, February 29, 2008

Garden plants: Hydrangeas

As Mother’s Day approaches, there are more and more displays of astonishing loveliness like this appearing outside flower shops and garden centres. Hydrangeas, like these, are forced into an unnaturally early bloom by placing them in temperatures below 65°F for six weeks to bring out the flower buds, then the leaves are stripped from the plant to force growth, and the plants are put into complete darkness between 33° and 40° for another six weeks! It does sound a bit like plant cruelty, doesn’t it?

And one real problem with receiving such glorious flowers as a gift is that hydrangeas are not keen to flower again after such treatment. To get them back into the flowering habit, you can prune the shoots back after flowering so that just two nodes (pairs of leaves) remain on each shoot. Then repot in a mixture of garden soil and compost and grow in dappled sun. Their natural condition is woodland, so it’s good to try and recreate that environment, where they are protected from strong winds by trees, and receive sunlight arriving through the overhead canopy.

Pruning isn't essential, especially in young plants, but once you see a lessening of the flowering, or the plant gets too big for its space, you can undertake some cutting back in spring as new shoots appear, removing one-third of the older, less productive stems at ground level and cutting back flowering stems to a strong pair of buds to maintain shape. Left unpruned, hydrangeas will continue to bloom but the size of the flower-heads will be reduced by the overcrowded stems. There’s one exception to this rule: Hydrangea paniculata needs to be cut back completely each spring.

Labels: caring for forced plants, hydrangeas, pruning hydrangeas

The All Seasons Gardener at 8:16 AM

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