In Februari 2007 I started some small experiments with what I call “bottle gardening“. I try to show that plastic bottles can be used as containers (see also “container gardening” informer messages on this blog).
The main objective is to use plastic bottles for vegetable production in the drylands in order to save a maximum of water for irrigation. Within the framework of the combat of desertification, it is important to get a maximum of agricultural or horticultural production with a minimum of irrigation water. Moreover, enhancement of food production should also be realized in the drylands and on relatively poor soils.
Should these experiments be successful, a myriad of bottles, otherwise littered and dramatically degrading the environment, could play a very interesting role in sustainable food production for the rural people.
Each bottle can easily be decapitated with scissors or a knife. Then, the top can be slipped inside the bottle and put as a conical cover over the perforated bottom. The bottle is now filled with a substrate. At home in Belgium, I did it with a nice potting mix to which some TerraCottem soil conditioner was added. TerraCottem is a waters stocking and fertilizing mixture (see http://www.terracottem.com). It offers the supplementary advantage to stock a large quantity of water and thus, keeps the substrate in the bottle moistened for a longer time (less direct drainage, less need to water the bottle regularly), resulting in a significant safe of water.
Five weeks after the start of the experiments, I feel quite happy with the results. I used different vegetable seedlings as test material : lettuce, cauliflower, parsley, lemon thyme and, later on, strawberry. I also used small, medium and big bottles. I watered the plants every 3-4 days with a very small quantity of water. No single plant died up to now.
My prognosis is that these plastic bottles can be used as “free” containers (no costs). In the drylands I would prepare a substrate with the local, mostly sandy soil, enriched with a bit of animal manure or compost and abit of TerraCottem.
I would also bury the bottles in a vertical position in the soil in order to avoid UV-degradation of the plastic, so that the same bottles can be used for a number of years.
It seems to me that this would be a good idea to get rid of all these littered plastic bottles. Maybe the same principle can be used with the classical plastic bags, which are now infesting nature all over the world.
Have a look at some pictures of my tests:
2007-03 : Bouteille décapitée – Sommet de la bouteille poussé à l’intérieur – Protection conique au-dessus du fond perforé
2007-03 : Bouteille remplie avec le substrat (terreau avec TerraCottem) – Le fond reste libre pour le drainage et l’aération. Persille en plein développement.
2007-03 : Une laitue et un choufleur se développent bien dans une bouteille en plastique.
2007-03 : La dimension de la bouteille ne semble pas être tellement important pour un bon développement.
2007-03 : Ma collection de bouteilles en plastique, petites et grandes, toutes vont bien.