The experiment was carried out during August 2005 to February 2006 in Department of Agronomy, Agricultural College and Research Institute, Madurai, Tamil Nadu. The experiment was laid out in split plot design. The treatment combination of 100 % RDF (40:60:50 kg NPK ha-1) + FYM (12.5 t ha-1) + Azophos (Azosprillum and Phosphobacteria) (2 kg ha-1) with GA3 100 ppm (spraying at 60, 90 and 120 DAP) registered significantly higher plant height and internode length of coleus plant. Application of 100 % of RDF + FYM + Azophos with panchagavya 3% registered higher number of laterals, number of leaves and stem girth. Application of 100 % RDF + FYM + Azophos with humic acid 0.1 % registered higher lamina length and lamina breadth, shoot dry weight and dry matter production. The combination of 100 % of RDF + FYM + Azophos with NAA 50 ppm registered significantly higher shoot fresh weight. The biometric observations were recorded at 60, 90, 120 DAP and at harvest. The biochemical parameters were also recorded at harvest. The major nutrients were analysed and the uptake was calculated. The qualities of coleus were tested at harvest. The treatment 100 % RDF +FYM + Azophos with humic acid 0.1% registered significantly higher leaf area index, chlorophyll content, crop growth rate, relative growth rate and absolute growth rate, tuber number, tuber length, tuber diameter, tuber volume, fresh and dry tuber yield per plant and fresh and dry tuber yield per hectare. Among the combinations, 100 % of RDF + FYM + Azophos with panchagavya 3% registered higher harvest index. The treatment 100 % of RDF + FYM + Azophos with humic acid 0.1 % registered significantly higher forskolin content and amount of essential oil. Application 100 % RDF + FYM + Azophos with panchagavya 3% registered significantly higher total alkaloid and starch content of tubers. The soil available nutrient status, nutrient uptake and soil organic carbon content were influenced by 100 % of RDF + FYM + Azophos with humic acid 0.1 %. Judicious combination of 100 % RDF (40:60:50 kg NPK ha-1) + FYM (12.5 t ha-1) + Azophos (2 kg ha-1) with humic acid 0.1 % (spraying at 60, 90 and 120 DAP) is recommended to get better yield with improved quality of coleus tubers, greater net returns and benefit cost ratio. Humic acid is slightly higher in price than panchagavya and hence next best choice is 100 % RDF (40:60:50 kg NPK ha-1) + FYM (12.5 t ha-1) + Azophos (2 kg ha-1) with panchagavya 3 % (spraying at 60, 90 and 120 DAP) to obtain similar productivity and quality of coleus tubers in addition to maintain better soil ecosystem leading to sustainable agriculture.

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