Calendar four: humid-tropical farms, and the cover crop that fits in every calendar
The three calendars above cover arid, Mediterranean and temperate farms. A fourth zone, the humid tropics of East Africa, coastal West Africa, South and South-East Asia and tropical Latin America, runs on a different base: perennial tropical grasses that are cut or grazed through the rains, with alfalfa and Super Napier on the drained, fertile ground and sesbania doing the soil work between stands.
Panicum (Guinea grass, Panicum maximum) is the tall, tufted perennial that East African, South-East Asian and Latin American dairies plant as their cut-and-carry base. It grows fast in heat and humidity, tolerates partial shade under trees and along bunds, and regrows quickly after each cut. Young regrowth taken every four to six weeks is leafy and palatable; stands left to go to seed turn stemmy and lose feed value, so it is managed on a cutting calendar like any other high-yield grass. On well-drained, fertile soil it is one of the highest-tonnage grasses available to a tropical farm.
Brachiaria (signal grass, Urochloa / Brachiaria species) is the grazing and sward grass for ground that panicum does not like: acid soils, low-fertility soils and, with the right species, land that waterlogs in the rains. It forms a dense, creeping mat that carries grazing animals, smothers weeds and holds soil on slopes, and it is the backbone of improved pasture across tropical Latin America and much of Africa. Dairies use it for the grazing block and the heifer paddocks while panicum, Super Napier and alfalfa supply the cut forage. The species and lot specification for the brachiaria we offer are stated on the certificate of analysis for that lot.
Sesbania (janter, Sesbania species) is the crop that does two jobs. As a fodder it is the soft, tender-leaved legume that sheep and goats take readily, giving two to three cuttings and around 150 to 200 maund per acre in 40 to 45 days. As a cover crop and green manure it is a nitrogen-fixing legume that grows on poor and saline land where little else will: sown between main crops or after a tired alfalfa stand is broken, and ploughed in at six to eight weeks before it flowers, it returns nitrogen and organic matter to the soil, improves structure on heavy or salt-affected ground and sets the field up for the alfalfa, panicum or Rhodes grass that follows. Farms reclaiming saline land often start with sesbania precisely because it establishes where the first attempt at alfalfa would fail.
These three sit alongside the Rhodes grass, ryegrass, berseem and Persian clover already in the programme, and they ship in the same mixed container under the same ISTA-tested, phytosanitary-certified document set. Tell the export desk your soil type, rainfall and whether the field is for cutting or grazing, and they will say which of the three belongs where.
In calendar terms: establish panicum and brachiaria at the start of the main rains so the stand is rooted before the dry season; cut panicum every four to six weeks and rotate grazing on brachiaria through the wet months; sow sesbania on any field that comes out of a main crop and has six to eight weeks before the next sowing, and plough it in before it flowers. That single habit, a green-manure crop in every gap, is what keeps a tropical forage rotation productive year after year without buying back the nitrogen as fertiliser.
