You will greatly improve your success in propagation by using the appropriate equipment and materials for the job.
What is Propagation?
Propagation is the process of growing new plants, either from seeds or vegetative growth (ie. taking cuttings, layering or dividing plants, budding and grafting).
For most newly propagated plants, the ideal environment is on a clean bench in a greenhouse where temperature, humidity and hygiene are strictly controlled. Some plants can be propagated just as easily in an unheated structure or even in the open ground. Amateur gardeners often do well placing pots on a warm window ledge or an enclosed verandah in their home. The most important requirement is usually to protect the plants from excessive heat or cold.
WHAT EQUIPMENT IS NEEDED?
Before you start buying propagation equipment, you need to decide what sort of propagation you want to do. You may simply want to divide up plants in a garden bed or raise plants from seeds. Or you may decide to try your hand at taking cuttings or maybe even grafting. Each method of propagation requires different equipment and levels of expertise:
Seeds – easy; no special skills required; either buy packets of seeds or collect your own; some basic equipment needed.
Division – easy; no special skills or equipment; requires only basic equipment.
Cuttings – easy to moderate; some skills required; equipment ranges from very basic to very sophisticated and expensive.
Grafting – moderate difficulty; specialist skills needed; basic to advanced equipment.
THE ESSENTIAL MATERIALS AND EQUIPMENT
FOR THE MORE ADVANCED HOBBYIST OR NURSERYMAN
The propagating medium is most commonly a free draining material such as sand or perlite, mixed with a water-holding material such as peat moss or well-rotted compost. A clean, free-draining mix will increase your propagation success rate. You can use a commercial propagation mix available from nurseries, or make your own.
There are many other alternatives though, including blocks of foam-like material called rock wool, that can be planted into directly.
You will be more successful when propagating if you use good quality tools SECATEURS
Secateurs are important for making clean cuttings. Blunt secateurs will create tears and other damage that will allow infections to enter the plant.
A budding knife is used for making cuts when you are joining two plants together to create an improved plant (eg. to improve the root system on fruit trees).
Containers should be selected according to the type of plant being propagated. To save space and to deter soil diseases, the container should be no larger than the plants will require before being transplanted. Seed trays, punnets and cell trays are all ideal for propagating seeds. They are comparatively shallow with a large surface area. Cell trays are particularly useful for keeping individual seedlings separate.Tubes and pots have a deeper shape. They encourage roots to grow downwards and propagators can insert cuttings deep into the potting mix. Select tubes and pots that have ridges on the inside walls of the container to discourage roots from circling. Only use clean, sterile containers. If using old pots, wash off any dirt and sterilise in a bleach solution.
Difficult to grow cuttings can be encouraged to produce roots by applying a rooting hormone to the base of the cutting before inserting it in the potting mix. Hormones are available from nurseries and supermarkets. Don’t apply too much rooting hormone as this may result in the cutting forming a callus without producing any roots.
GREENHOUSES AND OTHER STRUCTURES
Greenhouses, shadehouses, cold frames, cloches, pergolas and conservatories are all useful structures providing protection from weather extremes for propagated plants.
When planning a greenhouse consider the following:
Uses - what types of plants do you want to grow, and how many of them will be in the greenhouse at any one time?
Materials – different framing and covering materials provide different insulation, light transmission and durability
Orientation – how much sun do your plants need?
Water supply – will you be able to water your plants?
Electrical Power – do you plan to run lights, heaters, pumps, etc?
There are many different types of greenhouses, each with its own characteristics. If you plan to grow inside, choose the type of greenhouse that best suits the plants you want to propagate.
Short wall greenhouses have transparent material over the roof ( glass or durable plastics are most commonly used). Non transparent material such as timber or brick is used on the sides.
Long wall greenhouses have transparent material covering all of the walls and roof.
Tunnel greenhouses have half circle metal hoops arranged to form a tunnel shape. Transparent material is laid over this framework.
Lean-to greenhouses are attached to the side of another building. The "other" building provides insulation and a side wall for the greenhouse.
A COLD FRAME
One of the most useful "plant houses" for home gardens is a coldframe. It is a simple structure with fixed sides (eg. wood, brick, fibreglass) and a hinged top (eg. glass, fibreglass or plastic) to let the light through. The lid is at an angle so water can run off and the sun enters at nearly right angle. It can be opened and closed for access and ventilation.
They can be moved around to find the best spot, depending on requirements. Their disadvantages are that work is done at ground height and not on a bench, and the frame can heat up and cool down quickly.
Benches enable you to raise plants off of the greenhouse floor, keeping them away from disease and often in better light. They can be made from metal, wood or plastic, and usually include holes to allow water to drain.
Many plants will only grow at certain temperatures. Temperature control in the greenhouse can be achieved by:
Controlling the amount of sunlight with removable shade cloth or whitewash.
Opening or closing vents and doors
Operating watering or misting systems
The main types of heaters used in domestic and small commercial greenhouses are:
Unit heaters that burn fuels such as oil or gas.
Electric heaters that use a fan to distribute the heat.
Radiant heaters such as low energy infrared heaters.
Heating the benches or beds used for propagation will stimulate the formation of roots. This is more likely to occur when misting is used to cool the upper part of the cutting. Heat is supplied by either thin hot water pipes or by electric cables. Thermostats can be used to control the level of heat being produced.
Most cuttings need to be kept moist but not excessively wet. Softer tissue is more susceptible to drying out; so needs to be kept in a more humid environment.
The easiest way to water plants is with a watering can, hose or sprinkler. However, the droplets of water applied this way might displace propagating media or damage very soft plant tissues. Choose the appropriate type of nozzle for your sprinkler, hose or watering can and be careful when you apply the water.
Some dry areas can appear no matter how well an irrigation system is designed. Proper management must include checking for such dry spots and either moving the plants or hand watering these areas.
Seeds and cuttings can be automatically watered using either overhead, misting or capillary systems.
Overhead watering systems use sprinklers or sprays. These produce large water droplets that easily penetrate into the potting mix. However, these large droplets can damage leaves, displace cuttings and wash out seed.
Misting and fogging systems disperse tiny water droplets that increase atmospheric humidity as well as providing water for plants. To ensure a steady supply of water, they are usually operated by an electronic timer, moisture sensor or computer controller.
Capillary systems keep the potting mix moist by soaking up water through the bottom of the pot. Pots can either be stood in shallow trays (or saucers) of water, or on purpose-built benches that continuously pump water across the bench. They have the advantage of keeping the foliage dry, but can create problems with algae growing in the water.
Automated Systems - Watering, heating and humidity control systems all require resetting as conditions change throughout the year. They can also break down, so it is important that you do not over rely on automatic systems. Make frequent checks of their operation and the way they are effecting your plants.