The fibre of mesta is obtained from stem of Hibiscus sabdariffa var. altissima (n=36) and H. cannabinus (n=18), family Malvaceae. HS and HC denote varieties of the two species.   Area of Cultivation Within the jute belt, the yield of mesta is high in West Bengal, Bihar, Assam and Tripura. Outside the jute belt, the highest acreage is in Andhra Pradesh and the areas assuming importance are Dandakaranya, Orissa, eastern Madhya Pradesh, Maharashtra, Karnataka and Uttar Pradesh. Other states grow HC types over small areas, mostly for home consumption. Yield in the drier areas is a less than that in the humid ones.

A warm and humid climate suits both HS and HC varieties. Both these varieties grow in drier rainfed areas, the latter being more drought-resistant. In areas with 500-900 mm of rainfed, HC suits better by virtue of its shorter duration and faster growth. Neither varieties can withstand prolonged water-logging. Both the kharif crops and are sown in April-June with the first showers of the monsoon. Heavy, continuous rains and low temperature are harmful.

Both varieties of mesta grow on a variety of soils, including new and old alluvium soils. However, the rich loams give the highest yield, but acid soils are not suitable without amendment. With a high pH (above 7.0) of the soil, chlorosis appears in HS mesta. Both are unfit for low-lying areas, subject to inundation. The cultivators in India, in general, grow mesta in relatively poorer soils without much care as profits are marginal.

Soil for the mesta crop is prepared in much the same way as in the case of jute. HS when sown broadcast, requires 12 to 17 kg of seed per hectare. Seedlings, when 10-12 cm tall, are manually thinned in two installments to a spacing of 15-18 cm between plants. When raised in rows, seed is drilled 30 cm apart, the seed requirement being 10-12.5 kg per hectare. Seedlings are manually thinned to 12-15 cm apart in the rows. A minor adjustment in spacing is permissible on the basis of the fertility of the soil, rainfall and the nature of the soil.

HS variety of mesta fibre crop responds well to the application of nitrogen from 25 to 60 kg per hectare, depending on the soil type, the method of application and the rainfall. In drier areas, a basal dose of 20 kg of N has been found consistently giving 25 per cent higher yield. In areas having a better rainfall pattern, the quantity of nitrogen can be increased to 40 kg per hectare, and the application may be one-third of the basal dose and the remaining may be top-dressed in one or two installments between 45 and 70 days of sowing. Although the application to soil ensures best results, nitrogen as urea can be fed through foliage at the rate of 15 kg of N per hectare. Five kilograms of N in 100 litres of water is sprayed with a low-volume power sprayer. A single spray is effective between 30 and 75 days from the time of germination. A high pH of soil leads to chlorosis in HS varieties because of iron deficiency ; such soils are not to be used for growing mesta.

Harvesting

‘HS 4288’ and ‘AMV 1’ are harvested when 50 per cent of the plant population is in flower ; delayed harvesting give more fibre, but of coarser quality. ‘HC 583’ is harvested usually a month or more earlier. In Andhra Pradesh, plants are harvested by uprooting, which practice is not recommended ; in the jute belt, they are cut close to the ground, as in the case of jute. All HS types are of longer duration (180-210), whereas HC flowers in about 150 days after sowing.

Retting is done in the same manner as in the case of jute, but the low temperature and the paucity of water or both pose a problem. The harvested stems of both HS and HC can be stored under dry conditions for retting next season during the middle of the monsoon. The resulting HC fibre is better than that of HS. Retting in the current season, if possible, is always preferable.

The quality of the mesta fibre is judged on the basis of almost the same criteria as in the case of jute and the grading is done on the same lines, although the I.S.I. specifications are now due.