Smart greenhouses: the constant gardener
Image credit: Alamy, Getty images, PHILIPS LIGHTING, PARROT
Smart greenhouses mean plants are never alone to fend for themselves.
If you thought innovation in greenhouses ended with rows of polytunnels, think again. An electronic revolution is under way, with computers in charge of everything - from keeping disease under control to extending the growing season.
Although climate control can maintain steady growth a big hazard for greenhouse operators is disease. Sickness can spread quickly in the confined conditions. To nip it in the bud, drones swoop over the rows of plants to look for signs of stress, disease and damage caused by pests. They alert staff or, potentially, other robots to find the affected crops and pull them out or treat them before the problem spreads. Robots could also be used to harvest fruit and vegetables just at the point they are ready.
Lighting is the most obvious change with the shift to smart greenhouses. Digitally controlled LEDs can extend the growing day, supplementing the weakening sun in autumn and winter. LEDs use less energy than traditional lamps, making artificial lighting economical. The availability of specialist horticultural luminaires makes it possible to tune the colour. Purple is a popular choice for many plants that do not need the full spectrum of visible light to photosynthesise.
Some smart greenhouses exploit hydroponic growth techniques to control the supply of nutrients to the crops. Others use soil sensors that tell local irrigation pumps when to switch on and off to keep the soil moist enough to encourage growth.
Sensors are sprouting all over smart greenhouses. Those sensors will not only be used in the soil but also scattered around the framework to evaluate humidity, temperature and airflow to try to maintain optimum growing conditions and avoid situations that encourage the spread of unwanted fungi and other pests.