Luffa production opportunities in Canadian greenhouses
By Dr. Muhammad Arif and Dr. Peter K. Pauls
By Dr. Muhammad Arif and Dr. Peter K. Pauls
Luffa or Chinese okra (Luffa aegyptiaca Mill. and Luffa cylindrica) is typically cultivated in tropical and subtropical environments, but current research at the University of Guelph is looking into how this crop could be grown locally in greenhouses.
There are different uses for the crop depending on its stage of development. Their immature fruits are consumed as vegetables, while their mature fruits are used for household cleaning and personal hygiene.
Fresh luffa fruits are low in calories (20 kcal/100 g), and rich in antioxidants and vitamin A (123 mcg), C (12 mg) and iron (0.36 mg) (USDA National Nutrient database). Furthermore, luffa is consumed by some because of purported health benefits in relation to asthma, splenic enlargement and skin diseases. As the fruit matures on the vine, its fibrous flesh dries out, leaving behind a sponge. The sponges are sold commercially as a skin exfoliant and as cleaning supplies. Industrial uses of luffa sponges include ecofriendly marine steam engine filters, sound absorbers, door mats and table mats.
The luffa plant is an annual climbing vine that typically requires sandy loam soils, good sunlight and humid conditions for rapid growth in the field. Male and female flowers develop independently and indeterminately in clusters on the same plant. Luffa is a cross-pollinated plant and the bright yellow flowers attract pollinating insects like honey bees.
Approximately 16 per cent of Canada’s population is from regions of the world where luffa is used regularly as a main vegetable (Statistics Canada 2006 population census). According to the Food and Agriculture Organization (FAO), China, India, Japan, Indonesia, Malaysia, Philippines, Hong Kong, Brazil and the Caribbean are the major luffa-producing countries of the world. To meet demand, luffa is imported into Canada from Central America, Asia and Africa. Although the Canadian environment is temperate, other cucurbits such as pumpkin, squash and cucumbers, are successfully grown locally, suggesting that luffa gourds could be introduced into Canadian agriculture as well. Moreover, Canada has one of the world’s largest, most well-established, greenhouse sectors with 2,338 facilities covering a total area of 113.82 million square feet. Hoop houses are also being considered for extending the season and creating an environment favourable for luffa production in Canada.
The Department of Plant Agriculture at the University of Guelph collaborated with OMTEC Inc. in Ridgetown, Ont. to demonstrate the potential for producing luffa in a greenhouse using rockwool slabs and hydroponic cultivation for both ridged and smooth luffa. In a greenhouse, at 24°C, a relative humidity of 50 – 70% and a 16 h light/ 8 h dark photoperiod, the luffa plants grown in a hydroponic system required: ~3.0 litre nutrient solution/ day with pH ~5.5 and electric conductivity (EC) ~ 3.0. A large variation in plant growth and fruit production characteristics were noted among different luffa varieties. For example, flower initiation occurred between 41 – 66 days after planting of the different luffa gourds. Similarly, the first fruit was ready to pick in 60 – 87 days after planting in different varieties in a greenhouse containing a bumble bee hive from a commercial source. The immature fruit was ready to harvest in 6 – 7 days after pollination. The average fresh fruit weight ranged from 118 – 257 g; fruit girth ranged from 10 – 15 cm and the length varied from 20 – 60 cm. The number of fruit per plant ranged from 0 – 16 over a two-month fruiting period. The best yields were seen with 16 gourds/ plant and averaged 7 kg of fruit/ square meter of greenhouse space.
The initial work at the University of Guelph laid the foundation for longer term studies of the potential for commercial luffa gourd production in Canada, including studies of the genetics, breeding, agronomy of this crop, as well as manipulating the environmental conditions for high economical yields. The addition of a new crop to Canadian agriculture will increase the choices of vegetables available to consumers and could replace produce that is currently imported with locally grown product. This work could also add to the choice of crops that can be grown in rotation in greenhouses.
Acknowledgements: This research was supported by NSERC Engage grants. Muhammad Arif, PhD, is a research associate, and Peter Pauls, PhD, is a professor in the Department of Plant Agriculture at the University of Guelph.