It’s Fun And Often Not Difficult
By Clodagh and Dick Handscombe
Practical Authors and Gardeners living in Spain for twenty five years
The self propagation of plants is an economic way of producing new plants and can be an interesting and fascinating hobby, whether living in a house or apartment.
Luckily the warmer Spanish climate makes some propagations easier than it was in Northern Europe and in many areas without a greenhouse. Much of our garden was planted from our own plants raised from cuttings or seeds from our own or friend’s gardens. The cost of buying each plant from a garden centre would have been astronomic and we have some plants that are often not readily available.
This month we therefore review a number of practical ways of propagating and indicate what can be produced with relative ease by each method.
SPLITTING OF MATURE ROOT BALLS.
The easiest propagating method is to split large root clumps in the autumn or spring. This can be done with a wide range of perennials including herbs such as chives and marjoram, vegetables such as asparagus, bulbs such as agapanthus and tulbaghias, flowering plants such as rudbekias, coreopsis, chrysanthemums and gazanias. Often pots of the latter are already root bound when purchased from a garden centre and of a size too large for edging borders. We therefore immediately carefully remove the plant from its pot and prise the roots apart to produce up to a dozen or more good plantlets from a single purchased plant. Normally the several new plants will be immediately planted out in the garden although small plantlets can be grown on in pots before planting out.
ROOT CUTTINGS.
New plants of herbs such as mint and ginger and rhizomes such as irises can be produced by cutting off and planting up a short length of a healthy strong root without the need for any top growth.
LEAF CUTTINGS.
Pot plants such as epiphyllum, echeveria and streptocarpus can be easily raised this way. Remove any healthy young leaf and pin the leaf down on the surface of the soil in a plant pot or sink one edge of the leaf into the soil.
STEM CUTTINGS.
This is probably the most popular method used by both amateur gardeners and commercial growers for the reproduction of shrubs. Try it with oleanders, roses, grape vines, bougainvilleas, solanums, lantanas, hibiscus, begonias and many succulents. The cuttings can be rooted by planting up in pots or directly into a flower bed or special nursery corner of the garden. Rooting can be stimulated by dipping the cut ends of cuttings in rooting powder before inserting them into the potting compost.
For roses a useful Spanish trick is to cut a two centimetre slit in the end of each cutting and then inserting a dried sweet corn seed in the slit before planting the cutting.
REMOVING RUNNERS OR BABY PLANTS.
Some plants develop runners with small rooted plants on the ends. Strawberries, raspberries, spider plants and aloes are easily multiplied in this way.
LAYERING.
Many ground cover plants and shrubs with low branches can be multiplied in this way. Just peg a branch to the ground and cover the pegged area under a heap of earth for six months. When there is a good root ball cut off the rooted branch and plant up.
AIR LAYERING.
This slightly more difficult method can be easily used to produce new rubber tree or solandra plants. Make a slit in a healthy branch and then seal it within a plastic sleeve of dampened moss or potting compost. When a good root ball has developed, cut through the branch below and plant up the new plant.
GRAFTING.
Many fruit trees, roses and acacias are produced in this way. A cutting of the desired cultivar is inserted into cuts in a suitable host rootstock just before the sap rises in the spring. Unfortunately the several methods involved require a little practice, but at the second or third attempt you may create an orange tree that also has branches of lemons and grapefruits.
PROBLEMS THAT CAN OCCUR.
Although most of the above methods are easy for any keen gardener, there are a number of potential problems. However the following actions can minimise them:
Firstly, stem and leaf cuttings inserted in pots of compost can dry out. The best way of preventing this is to place a pot of cuttings inside a clear or semi-opaque plastic bag and then blow the bag up and seal. The cuttings can be left in this microclimate until strong new growth is observed.
Secondly, cuttings can rot off. The chance and extent of this can be minimised by washing and sterilising plant pots, sterilising the potting compost on a tray in an oven, adding sand or fine grit to the potting compost to achieve good drainage, adding a few drops of a fungicide to the watering can or spray before watering cuttings when first planted and when subsequently required.
Thirdly, don’t be tempted to plant new plants too early. Be patient and wait until there are signs of a good root ball and the weather has warmed up in the spring. Then harden them off for a few days in the sun before finally planting in the garden or in pots.
FROM SEED.
Lastly, one can propagate from seed, either from packets of seed or from seed saved from plants in your garden. The advantages include being able to tap into specialist seed catalogues that include many seeds of varieties of plants rarely available from nurseries, or in the case of vegetables, heritage or heirloom seeds no longer or never available commercially. Unfortunately growing from seeds is a topic too long for this column. However it is thoroughly covered in Section 6.13of our book ‘Your Garden in Spain – Planning, Planting and Maintenance’ and Sections 4.12 and 4.13 of ‘Growing Healthy Vegetables in Spain’.
These books can be obtained via high street and internet bookshops.
If you order from www.gardeninginspain.com you will receive a free copy of ‘Living Well from our Mediterranean Garden’.
©Clodagh and Dick Handscombe
February 2012.