What climate and soil does sweet basil need and can I grow it in a polyhouse?

Sweet basil is a warm season herb that likes temperatures roughly between 20 and 32 degrees C, full sun, and well drained loamy soil with pH around 6 to 7.5. It hates frost and waterlogging. In open field across most of India it grows well from spring through the rainy season, but in peak summer above 38 degrees C the leaves get small and bitter, and in winter cold it stalls. Because buyers of fresh culinary basil want a steady weekly supply all year, many growers near cities use a polyhouse or net house. Inside protected structure you get cleaner leaf (no rain splash, fewer pests), longer plant life, and you can supply through winter and monsoon when open field quality drops. A polyhouse costs money to put up, so only build one if you already have committed buyers who will absorb a year round supply. Sow in raised beds or trays, transplant at 4 to 6 true leaves, keep spacing about 30 by 30 cm, and harvest by pinching above a leaf pair so the plant branches and keeps giving flushes for several months.