Ginger is grown as a pure crop as well as an intercrop or in rotation with other crops. In Kerala it is grown as an undercrop in coconut and arecanut gardens, in coffee estates, and in rice fallows. In irrigated areas, ginger is grown in rotation with chilies, vegetables, groundnut, ragi, and maize. In Kerala as well as in Sri Lanka ginger forms a component of the homestead farming, and is grown mixed with a variety of crops. Ginger is a very successful crop component in intercropping and multicropping systems. It is intercropped with vegetables (such as cabbage, beans, cucumber, and lady’s finger), pulses (such as pigeon pea and black gram), cereals (maize and finger millet), oil seeds (castor, soybean, and sunflower) and with crops such as tobacco, pineapple, tapioca, taro, Discoria, and Amorphophallus. It can also be grown as a mixed crop with castor, finger millet, maize, and red gram. Chilies-ginger — mixed cropping is prevalent in many areas.
Nizam and Jayachandran (1977) in Kerala, studied the effect of seed rhizome size and varieties on the quality of ginger under open conditions and as an intercrop. Three sizes of seed rhizomes (5, 10, and 15 g) of ginger cultivars Kuruppampady, Maran, Nedu-mangadu, and Rio de Janeiro were planted in the open or as an intercrop in a 30-year-old coconut plantation. Nonvolatile ether extract (NVEE) was significantly influenced by rhizome size in open conditions; plants raised from 15 g rhizomes had significantly higher NVEE than plants raised from 5 or 10 g rhizomes. However, this effect was not observed in the intercropping treatment. In open conditions, plants raised from 5 g rhizomes had the highest crude fiber content, but when grown as an intercrop, plants raised from 15 g rhizomes had the highest crude fiber content. The cv. Kuruppampady recorded the highest NVEE under open and intercropped conditions.
Sankar and Swamy (1988), at Coimbatore, India, studied the ginger cultivar Rio de Janeiro grown as (1) monoculture, (2) as an intercrop in 2-year-old and (3) 6-year-old arecanut plantations. Average day temperatures in (1), (2), and (3) were 30, 28.3, and 27.9°C, respectively. The average light intensities available to the ginger plants were 104.81, 33.09, and 15.61 klx, respectively. Leaf area was highest in (3) and lowest in (1). Chlorophyll-a and chlorophyll-b contents increased up to day 150 after planting in (2) and (3), and up to day 180 in (1); thereafter, it declined in all cases. Rhizome yields in (1), (2), and (3) were 2.7, 9.2, and 13.5 t/ha, respectively.
Jasural et al. (1993) investigated the performance of ginger under rain-fed conditions in pure stands and as intercrops with 5-year-old poplars planted at three spacings (5 X 5,5 X 4 and 5X3 m) at Himachal Pradesh. The average illumination below the canopies was 53, 46, and 38 percent of incident radiation, respectively. The crop performed better as an intercrop than as a pure stand as measured by growth (height, tillers and leaves per plant, and leaf length and breadth), yield (rhizome length and breadth, yield per plant and hectare, and dry matter content) and survival. However, all parameters decreased as poplar spacing became closer than for the pure crop. For quality parameters, only the oil content in ginger showed significant differences. Among the poplar spacings, 5 X 4 m was the best. Singh et al. (1991) showed that ginger is a very favorable crop component under agroforestry. However, crop rotation is essential, as ginger depletes soil nutrients and due to the buildup of inocolum of rhizome rot pathogens. However, solanaceous plants should be excluded from such crop rotation.
Sujatha et al. (1994) noted that the highest sprouting percentage (100 percent) was recorded for cultivars Earanadan and Valluvanad when 26 ginger cultivars were grown in 3 X 1 m plots to be screened as intercrops for coconuts at the Regional Agricultural Research Station, Pilicode, Kasargod District, India. The highest fresh yields were recorded for cv. Kuruppampady (356.5 g/plant, 17.11 kg/3 m2 plot, and 57.05 t/ha), followed by Wynad, Mananthody, and Earanadan. The highest dry yield was recorded for PGS-667 (4.53 kg/plot, 15.5 t/ha), followed by Kuruppampady and SG-551.
In Sikkim, India, ginger is intercropped with mandarin orange (Citrus retkulata Blanco) and mixed with maize. Many farmers believe that raising maize and ginger together gives more yield than sole crops. Partial shade provided by the mandarin orange provides a congenial atmosphere for ginger. After harvesting of maize, ginger plants become exposed to more sunlight and that favors development of bolder rhizomes. Mixed cropping is more efficient and productive than sole cropping because of higher combined yields (of calories and proteins) and better energy use efficiency.
Manjunath et al. (1998) evaluated ginger as an intercrop in coconut gardens in the Goa region of India. In trials carried out between 1993 and 1996 cv. Sangli local was found to be the suitable annual intercrop for intensive management with May to June sowing, resulting in good yields and the highest net returns. Intercropping increased coconut yields from an average of 13 nuts/palm before intercropping to 39 nuts/palm after 3 years of intercropping.
Sharma and Bajaj (1998) undertook studies to improve ginger yield against infection with Pratylenchus penetrans, Meloidogyne incognita, Helkotylenchus dihystera, and Tylencho-rhynchus mashhoodi in Himachal Pradesh, by intercropping with bell pepper, Capsicum annum, in eight different treatments. Intercropping of one rhizome of ginger X one plant of bell pepper gave the highest ginger yield (600 g/rhizome). This treatment was completely free from P. penetrans and M. incognita. All treatments with bell pepper plants equal to or higher in number to that of ginger rhizomes had higher ginger yields than treatments with ginger alone or with fewer bell pepper plants. In the former, populations of P. penetrans and M. incognita were lower than in the latter treatments. Pegg et al. (1969) recommended beans, cucurbits and strawberries as suitable crops for rotation to minimize nematode problems.
Kandiannan et al. (1999), investigated the effect of intercropping ginger with maize under rain-fed conditions. The crops were planted in June on raised beds (3X1 m): ginger at 25 X 30 cm and maize at each corner of the raised bed. Maize was harvested 90 to 100 days after planting and ginger 8 months after planting. There were no significant differences in the percentage of sprouting, total number of tillers/bed, and fresh rhizome yield between ginger grown alone and with maize, indicating that intercropping had no deleterious effect.
E. V. Nybe and N. Mini Raj “Ginger Production in India and Other South Asian Countries” (2005)