Have you ever wondered how professionals find their material for reproducing plants?
Of course, they have to have stock plants for taking cuttings. Cuttings are often taken from material that might have been grown on in 1 litre pots for example ready for re-potting and sending out to the garden centre.
Nurserymen will also plant shrubs - especially popular varieties that are good earners - in stock beds near to or around the nursery that are deliberately let to grow so that the semi mature wood can be reaped and struck for producing new stock.
There is also the collection of seed but if the plant is a cross this will not always produce the results that are desired with the seed often revering to it's original form.
This brings me onto one of my favourite and I think one of the most interesting ways to reproduce using a host shrub - Layering.
A layer is fairly easy to understand by it's definition. Basically, it is a means of attaching a living stem to the soil by means of a peg or stone to encourage roots to develop and break roots from the stem.
The roots then anchor the stem and in time become self sufficient so that the new layered plant can be detached and establish independent of the host plant.
There are several types of layer:
Simple layering - just take a healthy branch (not too old) and pull it down to reach the soil. Scrape back the soil until you have created a scoop. Bend or twist the stem to stress it. Be careful not to sever the cambium. Place the stressed stem into the scoop and peg in place (I prefer a forked stick cut from the hedge) and cover with the soil you scooped away making sure there is not a lot of fibre present.
Make sure that there is at least 6-10 inches of stem showing and the leaves that remain are fresh and turgid. This method works well with Rhododendrons and Azaleas, Ribes, Forsythia, Cornus, Box, Climbing Roses.
There is a variation of the above simple method (sometimes called serpent layering) where you can use a long shoot, say from a vine, Honeysuckle or Wisteria and produce several plantlets along the same stem.
Tip Layer - Pretty self explanatory. Prepare the scrape the same way but make a little deeper. Push just the end of the branch into the scrape and cover with soil. Once the roots break a new shoot will emerge and develop into a leader. Pare away from the host when you feel it is sufficiently independent.
Stool Layer or Stool Bedding - Force roots from the stem above the nursery mark by pushing fresh soil against the trunk. Once the roots break from the bark you can pull away the soil and sever the new rooted stock away from the host.
This is a favourite method for fruit producers especially Apple. The vigorous root stock is then grown on and used for grafting. Magnolias, Cotoneasters can be reproduced this way too.
Air Layering - This one can be a bit tricky and I have had a lot of failures doing this with the success rate being about 5/10. Use one year wood if possible but for best results do not try it on wood older than 2 year (I am not saying it will not work on older but it gets harder).
Pick a stem and using a sharp pruning knife, make an upward cut of about 1 inch in length cutting through two thirds of the wood. Insert a cocktail stick or matchstick inside the cut to keep it from callousing and repairing itself. If you can lay your hands on some steri-strips then bind a couple around so it holds both parts together and the stick in place.
Then, take a large ball of sphagnum moss and soak it in water. Fold this moss around the cut so that the moss touches the stem all the way round. Now, using either a plastic bag, cling film, or metal foil, wrap it round to form a waterproof bandage. Secure both ends with some electrical tape or raffia string.
Then wait and watch to see if the end dies back or continues to grow. You mat see the bag swell but once you are sure the layer has taken you can remove the plantlet from the host and pot it up as normal.
This works well with Rhododendrons, Azalea and Magnolias and for indoor the Ficus elastica (Rubber Plant) which those of you who attended Horticulture college will remember is pretty mus what all of us try air layering on for the first time.
Some plants that grow using a a Stolon (referred to as Stoloniferous) are easy to propagate. A Stolon is an overground stem and will look to root by itself. Strawberry plants are typical of a plant that reproduces with a Stolon. An Ivy will reproduce naturally as it searches to anchor itself using a aerial roots (anventitious). An Ivy will not necessary need soil as it climbs a tree or solid structure and these adventitious roots can extract moisture and nutrients from the surrounding air or host.
Of course, and we can expand on this, A Rhizome is a stem that grows underground and is referred to as Rhizamatous
You may be interested in How to layer a Virginia Creeper.
Comments