Ensuring all-year round availability of high-value vegetables through container gardening under protective cultivation
Before, the idea of growing vegetables in urban setting seemed unrealistic. The lack of available space, immense pollution and extremes of weather have daunted potential vegetable growers to go into this kind of production system. But with the advent of urban agriculture, specifically the production of vegetables in containers under protective structures, optimization of land-use and production using climate-controlled techniques can now be opportunistically addressed. Also, with scientific advances, urban agriculture is now able to address the challenge of supplying nutritionally adequate and safe food to city dwellers.
Dr. Renato C. Mabesa of the Department of Horticulture of the Crop Science Cluster of the College of Agriculture, University of the Philippines Los Baños (UPLB) is leading a project titled, "Protective Structures for High Value Vegetable Production in Containers as an Approach to Urban Agriculture", with funding support from the Department of Agriculture-High Value Commercial Crops (DA-HVCC) Program and the Bureau of Agricultural Research (BAR). The project aims to provide growing urban populations with year-round access to nutritious food by growing high-value vegetable crops in containers using protective structures and covers right in the towns and cities.
Production of vegetables in containers as an approach to urban gardening is not entirely a new concept for this has been practiced before. "This is like backyard gardening but vegetable crops are exclusively grown in containers instead of planting them in the ground. Vegetable container gardening can be considered a viable sustainable production method", according to Dr. Mabesa, "since it promotes the re-use of materials that are abundant and considered as waste including old rubber tires, styropor, plastic bags and bottles, tin cans, and scrap metal."
Protective cultivation, on the other hand, is a cropping technique wherein the micro-climate surrounding the plant body is controlled partially or fully according to the requirement of the plant species during their period of growth. Using productive structures and covers such as polyethylene plastic and fine agricultural nylon net helps in improving the quality of vegetables grown in containers.
"This cropping technique is very appropriate in the Philippines because our extreme weathers easily affect the outcome of our vegetable produce. Protective structures and covers serve as physical safeguards against extreme environmental conditions such as excessive rain and high temperatures," Dr. Mabesa explained.
The first phase of the project demonstrated the production of different kinds of vegetable salads, particularly lettuce, in containers under protective structures. "This was done in various sites of the CALABARZON (Cavite, Laguna, Batangas, Rizal and Quezon) area. Phase two of the project studied the performance of various Brassicas (also called Cruciferae) such as cabbage, cauliflower, broccoli, and kale in various sites of CALABARZON and Metro Manila."
The project is now on its third phase focusing on the performance of "pinakbet" crops such as tomato, eggplant, lady's finger, stringbeans, bitter gourd, and squash. Results from the first two phases have been incorporated in the third phase particularly in the use of protective structures and containers. "For the protective structures, we used protective high tunnels and iron stands for durability and sustainability. Also, instead of plastic pots we have metal shelves with bamboos for planting area due to the immediate availability of the material," Dr. Mabesa expounded. Another modification is on the structure itself making it smaller (10 sq.m) to accommodate limited spaces making the technology more cost-effective.
In its Phase 3, the project concentrated on the Gawad Kalinga and Bahay ni Juan areas with informal settlers. "We need to teach them the technology of making available home-produced food and be able to sell them through informal markets thus providing them an additional source of income."
Dr. Mabesa is hopeful that, given the projected increase of populations in urban areas in the next 25 years and its consequential effects on urban poverty and food insecurity, protective cultivation technology can play an important part in addressing these issues.
"With proper care and maintenance, container growing of high-value, all-year-round vegetables under protective cultivation is an ideal way of providing urban dwellers with healthy and nutritious food," Dr. Mabesa concluded.