Want chemical-free vegetables? Vertical farming might be the answer


These vertical farming towers developed by the Telangana State Centre of Excellence may be the answer to the increasing demand for chemical-free leafy green vegetables

The Telangana State Centre of Excellence (TSCoE) in Jeedimetla feels like an oasis, in contrast to the barren highway that leads to the area and the humble residential colony in its vicinity. The 10.35-acre facility managed by the department of horticulture is a hub of experiments for the cultivation of vegetables and flowers.

In one of the poly houses covered by a UV-stabilising film, more than 800 PVC pipes have been converted into vertical farming towers. Each of these pipes has been filled with a mix of coco peat, red soil, neem cake, vermicompost and micronutrients that help plant growth. Each pipe has more than 20 slots from which small branch-like extensions emanate, it is in these that green leafy vegetables are grown.

The CoE designed and tested such prototypes in December 2018, approved by the department of horticulture authorities and a technical committee of agriculture experts; it has so far grown coriander, amaranthus, bacchali (Malabar spinach) and palak (spinach). At the moment, the 800-plus towers grow spinach, some of them ready to harvest.

A retail counter near the entrance of the premises sells fresh greens and vegetables grown at the center and it’s a big hit with the neighbourhood. Palak is sold at ₹40 per kg, double the price of the wholesale market, but there are many takers since these greens are free of chemical pesticides. There have been days when the center sold 400 to 600 bunches of leafy greens.

While vertical ornamental gardens add aesthetics to premises, vertical farming is more utilitarian. CoE intends to encourage residential colonies in urban areas and farmers at the district and Zilla Parishad levels to grow more greens using vertical farming.

The CoE feels that having several small crop colonies in urban pockets and rural areas might help meet some of the growing demand for vegetables in the state. Leafy greens, tomatoes, brinjals, chilies, and okra, for instance, can be cultivated in balconies and terrace gardens to meet individual home needs.

In addition, enterprising farmers in both urban and rural areas can do vertical farming to grow greens that meet the needs of their neighbourhoods, believes the CoE. “Green vegetables are the need of the hour. They perish easily and don’t withstand long-distance transport. A lot of greens available in the market are also laced with chemical pesticides. There’s an increasing awareness today about safe food. Growing your own greens will ensure safe food and reduce food miles,” says K Latha, assistant director of horticulture, CoE.

Traditional farmers can use vertical farming towers to step up the yield. “In flat-surface farms, it’s tough to harvest green leaves during monsoon. Leafy vegetables can be harvested every 25 to 30 days, so ideally you can aim for 12 harvests a year. In flat cultivation farmers only manage eight or nine harvests. Using these towers and a poly film roof, greens can be grown all around the year,” she says.

The coco peat and nutrient mixture in these towers can be replenished after three or four harvests to get quality produce. To counter weeding, the CoE uses a weeding mat on the ground. Small outflow pipes from each of the towers drain excess water.

To make vertical farming economical, the CoE uses non-ISI mark PVC pipes that cost ₹400 to 500 each, as opposed to ISI-certified ones that cost around ₹5000. However, the non-ISI pipes stand the risk of damage when exposed to prolonged heat. The UV-stabilising poly film roof counters this problem.

Latha points out that there are several smart vertical farming methods worldwide, including those that use hydroponics and aeroponics. “There are various designs of vertical farming towers too, across the world. The indigenous technology we developed is one of the methods,” she says, signing off.

Courtesy: The Hindu