Is hydroponics sustainable?
The hydroponic re-circulating system is cleaner than conventional agriculture because it requires only the amount of nutrients which will be taken up by the plants, and these remain contained in the system until they are completely used up. In general the main problem with using artificial nutrients in soil is not what the plants use but what they don't use - as much as 90% of the more soluble nutrients can be leached out of the soil by rainfall or irrigation before the plants have a chance to use them. This leachate ends up in the ground water and contaminates rivers and lakes leading to algal blooms, deoxygenation and ultimately is fatal to fish and other animals. Also, salts can build up in ground water reserves making them too saline to use for drinking. In a closed recirculating system such as hydroponics, the nutrients are conserved in the tank and there are no losses to the environment. Virtually all the nutrients in the system get used up by the plants which also means that the nutrients are used more efficiently: hydroponics uses far fewer nutrients overall than a normally fertilised crop in soil.
At the Achiltibuie Garden we have decided to use renewable energy to power the pumps needed to circulate the water and nutrients to the plants in our keder growing house. We have a "solar panel trailer", infact the very same one which was recently featured on "Monty Hall's Great Escape", to charge batteries to power the pumps. We are also harvesting rainwater to supply our hydroponic systems and to water our raised growing beds and outdoor garden during dry spells.
The cost of road transport, both financial and environmental, can be very high in remote areas such as our location in Wester Ross. Growing crops using hydroponics for local distribution is helping to reduce the amount of food that has to be transported into the area. On a wider scale, there is often an enormous environmental cost involved in getting food products from the grower across the world to the end user due to the large amounts of fuel needed. Producing food locally using hydroponics may be more sustainable than relying on imported produce.
With consumers now becoming increasingly aware of how the food they buy is produced, along with their concerns for the rising costs in both financial and environmental terms, many are "growing their own". Hydroponics provides them with the opportunity to grow fresh, flavoursome and healthy produce whatever space they have available - from a windowsill to a greenhouse.