There are six agroclimatic zones in West Bengal based on meteorological, altitude, soil, and topographic factors. These zones include the Hill Zone, Terai and Teesta Alluvial Zone, Gangetic (New) Alluvial Zone, Vindhya (Old) Alluvial Zone, Laterite and Gravelly Undulated Zone, and Coastal Alluvial Zone. Each zone has different average annual rainfall levels and soil types and supports the cultivation of various crops suited to its particular climate and conditions.

1. Agroclimatic Zone(s) in West Bengal
Agr’l. crop-season is of three kinds, viz. pre-kharif(mid-Mar. – mid-Jun.);
kharif(mid-Jun. – mid-Oct.); rabi(mid-Oct. – mid-Mar.) .
There’re six agroclimatic regions in W. B. depending upon meteorological
elements cum factors (eg. sunlight, temp’r. , precipitations(snowfall &
rainfall); humidity; etc.) & altitudinal factors along with edaphic as well as
topographic factors, which are as follows viz. –
Hill Zone :-
Entire Darjeeling district except Siliguri sub-divn. & northern fringe of
Jalpaiguri district belong to given region. Here rainfall is 250-350cm/yr .
There’s brown forest soil(4.2-5.8) in given region .
Maize, Potato, cabbage, cauliflower, bean, pea, chilli, ginger, blackpepper,
cardamom, cinnamon, turmeric, mandarin-orange, tea, peach, pineapple,
tulip, gladiolus, rhododendron, orchid, tuberose, marigold, etc. are the main
crops. However, rice, wheat to some extent are grown also in relatively lower
altitude .
Terai & Teesta Alluvial Zone :-
Entire alluvial plains of Jalpaiguri & Coochbihar, Siliguri sub-divn. and
Islampore, sub-divn of N.-Dinajpore belong to given region. Here rainfall is
210-230cm/yr .
There’s sandy-loam alluvial soil(4-6) in given region .
Potato, tomato, cabbage, c.flower, brinjal, spinach, onion, chilli, garlic, ginger,
turmeric, cumin, aniseed, coriander, m.-orange, pineapple, jackfruit, mango,
banana, tea, betelnut, gladiolus, tuberose, marigold, rose, chrysanthemum,
aster, etc. are the main crops. Cereal, pulse, etc. also are grownto some extent
due to micronutrient deficiencies .
Double cropping system is so common under this rainfall condition from
Mar-Dec, as pre-monsoon shower starts from March .

2. Gangetic(New) Alluvial Zone :-
Entire Nadia and part of Malda, Dinajpore, Murshidabad, Burdwan, Hooghly
& 24-Pgs belong to given region. Here rainfall is 150-160cm/yr .
There’s fertile loam, clay-loam, clay type soil(6.9-7.2) in given region .
Rice, lentil, S.cane, mustard, seasame, jute, potato, tomato, egg-plant(brinjal
plant), cucurbits(pumpkin, pointed gourd[parwal], cucumber, bittergourd,
cabbage, C.flower, bottlegourd, carrot, radish, chilli, onion, cumin, b.-cumin,
coriander, ginger, mango, banana, guava, litchi, jackfruit, papaya, walnut,
coconut, sapota, tuberose, rose, chrysanthemum, dahlia, jasmine, marigold,
etc. are the main crops .
Vindhya(Old) Alluvial Zone :-
Western part of Murshidabad, Bankurah & E.-Midnapore, eastern part of
Birbhum & Hooghly and central Burdwan belong to given region. Here
rainfall is 140-150cm/yr .
There’s sandy-loam, clay-loam, loam type of soil(7-6.5) in given region .
Rice, lentil, mustard, G.nut, potato, egg-plant, cucurbits(same as Gangetic,
besides ridgegourd ), cabbage, C.flower, ginger, turmeric, chilli, coriander,
cumin, cashewnut, coconut, sapota, mango, guava, litchi, banana, W.nut,
jackfruit, rose, tuberose, marigold, jasmine, dahlia, etc. are the main crops .
Laterite & Gravelly Undulated Zone :-
Entire Purulia, major part of Bankurah, western part of Birbhum, Burdwan
& W.-Midnapore and eastern Maldah, and part of S.-Dinajpore & E.-
Midnapore . Rainfall is 120-130cm/yr .
There’s red lateritic and gravelly soil(5-6) in the region .
Rice, maize, potato, tomato, cucurbits(same as formers), okra, arum, S.potato,
carrot, radish, cabbage, C.flower, bean spinach, onion, turmeric, ginger,
coriander, cumin, chilli, ber, mango, custardapple, C. nut, coconut, papaya,

3. Sapota, dahlia, jasmine, marigold, chrysanthemum, rose, etc are the main
crops .
Coastal Alluvial Zone :-
24Pgs,southernpart of Howrah & E.-Midnapore belong to given region. Here
rainfall is 160-180cm/yr .
There’s sandy-loam, loam type of saline-alluvial soil(6.5-8.5) in given region .
Rice, mustard, knolkhol, arum, chilli, potato, spinach, tomato, brinjal,
C.flower, coriander, aniseed, turmeric, mango, litchi, guava, banana, sapota,
W.melon, coconut, C.nut, W.nut, papaya, rose, jasmine, tuberose,
chrysanthemum, dahlia, etc are the main crop .