Season and Field preparation
Sweet potato can be grown in loamy soil with a pH range of 5.6 – 6.6. It requires a warm and moist climate.
June – July and September are highly suitable for planting.
Preparation of field
Plough the field to fine tilth. The soil depth should be atleast 30 cm. Form ridges and furrows at 60 cm apart. Sweet potato can also be grown in beds.
Preparation of cuttings
The cuttings should be 10-15 cm in length with 2-3 nodes and to be collected from matured vines aged 3 months and above. Dip the vine cuttings in a solution by mixing 400 g of Azospyrillum in sufficient quantity of water.
Plant the terminal vine cuttings (80,000/ha) at 20 cm spacing.
Irrigate is done before planting, again on 3rd day and there after once in a week. Stop irrigation one week before harvest.
Application of fertilizers
Apply 25 t/ha FYM and 20:40:60 kg NPK/ha as basal and 20:40:60 kg NPK/ha after 30 days. If 20 kg/ha Azospirillum is applied, apply only 2/3rd dose of N. It is preferable to apply N and P in the form of DAP (Diammonium phosphate).
The field should be kept clean by hand weeding till vines are fully developed. Earthing up can be done on 25th, 50th and 75th day after planting. The vines are lifted and turned on 50th and 75th day after planting but before earthing up to prevent root formation at nodes and to make the originally formed roots larger. Spray Ethrel five times at 250 ppm at fortnightly intervals commencing from 15 days after planting.