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Plant propagation

Help solve your gardening problem. Here are the answers to some commonly asked gardening questions about propagating plants with hints, tips and advice.

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I would like to propagate Surfina petunias from cuttings this autumn. Can you advise me step by step how to do it?

It is better to take the cuttings in August not the autumn or, if you can overwinter the main planst frost free, do it in spring.

Choose healthy shoots and preferably those that aren’t flowering. Take 7.5-10cm (3-4in) cuttings just below a leaf, remove the leaves from the lower half of the cutting and dip the end in hormone rooting powder or liquid.

Then insert the cuttings in pots of cuttings compost - you can make your own from equal parts of peat - or peat substitute - and vermiculite. Cover the pots with a polythene bag and place somewhere warm and sheltered, but out of strong, direct sunlight. Or, better still, put them in a propagator with bottom heat. They should be ready to pot on in a couple of weeks.

Is it possible to take cuttings from clematis?

It is possible, but clematis aren't the easiest of plants to grow from cuttings, but the following will help.

Cuttings are best taken in summer (July/early August) using the current year's growth.
Take cuttings from the middle of a shoot.
Trim to above a leaf joint and half way between the next lowest one.
Remove one of the pair of leaves.
Treat bottom end with hormone rooting.
Insert in pots of gritty compost.
Cover with polythene bag or put in propagator.
Cuttings will need a bottom heat of about 18C (65F).

The best way to reproduce clematis is through layering.

Choose a supple stem or two that can be pulled down to the ground.
Make a shallow slanting cut through the bark on the underside where it touches the ground, wedge the cut open with a match or similar and apply hormone rooting powder to the cut.
Peg the shoot into a small pot of compost which has been sunk into the ground.
Tie the stem to a small split bamboo cane.
Weigh the branch down with a pebble or small stone.
It may take six months to root, but it is the most successful method.

I have managed to get a cutting of a clematis to root. It is on the windowsill as I do not have a greenhouse. What should I do with it now?

The important thing to remember about plants (even hardy ones like clematis) is that, like people, they don't like extreme changes in weather/temperature.

If you are growing the plant indoors, the important thing is not to let it get too warm; a cool room is perfect so that it stops growing; in nature they wouldn't grow in the winter. Make sure the compost is kept moist.

Then you have to harden it off (like you would bedding plants) so it doesn't get a shock from being outside. Do this in late winter so that it can be planted out in say March.

What is the best way to propagate rhododendrons?

It is possible to take cuttings from rhododendrons but they are not easy to root. Your best bet would be to layer the plant.

Choose a supple branch low down on the plant which is possible to pull down to the ground.

Make a shallow slanting cut through the bark on the underside where it touches the ground, wedge the cut open with a match or similar and apply hormone rooting powder to the cut.

Peg the shoot into a small pot of ericaceous compost or peat and sand mix which has been sunk into the ground.

Weigh the branch down with a pebble or small stone.

It may take six months to root but it is more successful than cuttings.

 

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