New plant cloning is best done in winter


aAs someone who grew up in the tropics, surrounded by light and life all year round, I’ll probably never get used to the long, slow fall of a garden as we inevitably slide into UK winters . However, over the past 20 years, I’ve developed some coping mechanisms to help me get my gardening fix. From winter flowering houseplants to autumn seed sowing, there are some simple ways to see the promise of active growth and new beginnings, even when it’s foggy outside. Perhaps, though, nothing is quite as effective as the wonders of life chopping hardwood.

Like most forms of vegetative propagation, hardwood cutting involves deliberately damaging a plant which, in its efforts to repair itself, sends up new roots and leaves to create a perfect genetic clone. Since this type of harvesting is done when the plant is dormant – any time from mid-autumn to late winter – they are usually under the pressure of active growth in the summer that creates these cuttings. There will be less shock. Easiest to do, my mind. All you need is a pair of secateurs, a hoe, and, depending on your soil type, a little sand to achieve cloning.

First, using sharp, clean secateurs, cut off a few short 20–30 cm segments of young stems that have grown in the past year. The great thing is that these can be just off-cuts from the autumn pruning you’d be doing anyway, which means you can create free plants from plants that would otherwise be just garden waste. Excellent candidates for this treatment include fruiting shrubs such as gooseberries and currants, as well as flowering wonders such as hydrangeas, roses and viburnums, and leafy trees such as willows and dogwoods. Climbers like jasmine and honeysuckle will also work.

Now, lay your cuttings on a table and remove the bud at the end of each section, as this will result in dense, bushy growth when your cuttings germinate. Making this cut at an angle is a useful tip, so when it comes to planting you’ll know exactly which end goes up, which is the only important thing to get right.

Then all you have to do is dig a narrow trench—it should only be deep enough to bury the cutting (up to the pointed end) by two-thirds—and place your cuttings in it, spacing them about 15cm apart. If you’re growing on really heavy soil that’s prone to waterlogging, you might want to put about 10cm of sand at the bottom of the trench, but over most other types of soil I don’t think there’s a huge advantage. Finally, fill the trench with soil and then water liberally.

All that’s left now is to be patient, as these will take about 12 months (depending on the species) to form a strong root system. Keep the trench from drying out in the spring and summer, and by this time next year you’ll have your own little clone army in return for very little work.

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