After ground level pruning, chemical weed control measures must be taken up to avoid smothering effect of weeds on regenerating tea bushes. Diuron, Simazine, Dalapon, Glyphosate, 2,4-D and Gramoxone are the main herbicides used for control of weeds in tea gardens. Refer to the detailed leaflet ‘no. 2’ issued last year on "Weed Control in Tea" for quantities of herbicides and their methods of application.
However, for ready reference see the following schedule of herbicide quantities and mixtures. For one acre use 200 liter water for preparation of solution. Post-emergence spray of herbicides may be done in May/June and repeat application is done in September.
Pre-emergence herbicides: Sprayed after cheeling the ground clean on moist soil. Diuron 1 kg. or Simazine 1.5 kg.
Diuron 250 gm. + Gramoxone 500-650 ml. Simazine 1.5 kg. + Gramoxone 500-650 ml. Dalapon 1.75 lg. + 2, 4-D 500 gm; Glyphosate 1 liter; 2,4-D 500 gm. + Gramoxone 500-650 ml. Apply herbicides with care preferably with spray-guards to avoid drift damage to tea plants.
Major plant nutrients are not prent in sufficient quantities for optimum growth of tea plants. Nitrogen (N) promotes quantity and speeds up the leafy growth. Phosphate (P) helps in promoting root growth while Potash (K) promotes vigour, helps metabolism and gives strength to plant to fight out drought conditions. Zinc a micronutrient, is also needed for healthy growth.
It is advisable to get soil tested of tea gardens and then follow the recommendations. Leaflet ‘no. 1’ on Fertilizer use in Tea Gardens of Himachal Pradesh released last year gives a general recommendation to use 36 kg. N, 36 kg P2 O5, 36 kg K2O and eight kg. Zinc sulphat per acre. See details in the leaflet mentioned above. Place the fertilizers about 15 cm (6") away from the base and it is preferably lightly forked in the ground. Wrong application of fertilizers can do more damage than good to tea bushes as shown in the pictures below.
CAUTION: Do not throw fertilizers on tea bushes.