Greenhouse Equipment and Greenhouse Watering Systems
Greenhouse Watering Systems
The importance that automatic watering systems assume, must relate to the time you have available to attend to your plants. For anyone who has to leave plants unattended for any length of time, an automatic watering system may be a good investment in the long term.
If the bench is made into a shallow trough, and the plants placed on a bed of sand, kept moist, the plants will probably take all the water they require by capillary action. Alternatively the bench can be lined with polythene and a special capillary mat or blanket placed on it and kept permanently moist by various methods. The two main methods of keeping sand or blanket moist are a reservoir system at one end of the bench, or tubing laid between the plants, with fine holes from which the water dribbles.
Unless there is adequate greenhouse ventilation, plants will soon suffer. The temperature can soar quickly in sunny weather, and on cool, damp days a lack of ventilation can lead to moist conditions that are ideal for the rapid germination of disease.
Automatic ventilators are not difficult to fit, and are efficient and trouble-free in operation. They normally work by the expansion or contraction of a liquid in a cylinder attached to the ventilator.
Most operate a conventional type of window, but some open and close a louvre.
In a greenhouse 2.4m (8ft) long, at least two roof ventilators will be required, and ideally there should be a third ventilator low down in the side or at the end.
Most gardeners settle for a ‘permanent’ greenhouse shading — a white or green wash applied in early summer and removed in autumn.
Roller blinds can be fitted, but they tend to be expensive and still need someone to operate them. This can also be automated, but such equipment must be regarded as a luxury.
A simple heated propagator merely provides a humid atmosphere in which seedlings can germinate or cuttings root. To make it most effective, however, it should have some form of heating, usually-warming cables. An expensive version may have a mist unit to ensure a sufficiently moist atmosphere for the most difficult cuttings.
It is not difficult to make one’s own propagator from a suitable box lined with polythene. The thermostatically controlled soil-warming cables are buried in sand, and an air-warming cable used round the side above compost level to increase air temperature slightly. A sheet of glass over the top maintains humidity.
Although a cold greenhouse can be run with the minimum of equipment, if it can be attended to during the day, a heated or unattended greenhouse must be suitably equipped. Basic equipment includes a heater a fan heater and oil heater, a ventilating fan, shading blinds, a minimum-maximum thermometer and a heated propagator
Greenhouse Mist Units
For difficult cuttings, a greenhouse mist unit can make all the difference between success and failure. Used with a moisture-sensing device, it emits a fine mist whenever the leaves are likely to become too dry.