Coleus
Botanical Name- Coleus forskohlii
Family – Lamiaceae
TNAU- medicinal coleus CO-1
Soil –
Red sandy soil and sandy loam soil are highly suitable. Soil drainage is essential and hard pan and water logged soils should be avoided.
Climate –
The plant is sun loving and grows well in tropical regions.Suitable for plains and lower hills. Requires 70 cm annual rainfall
Suitable for plains and lower hills. Requires 70 cm annual rainfall
Propagation
Terminal three to four nodal cuttings measuring 10 cm length is used. Cuttings are
planted at 60cm x 45cm spacing with total plant population of 37,000 plants per hectare.
Land Preparation
Apply 15 t FYM/ha. Ridges are formed at a spacing of 60 cm. Cuttings have to be
planted at a spacing of 45 cm.
Nutrient Management
The nutrients NPK @30:60:50 kg/ha have to be applied in two split doeses at 30 and
45 days after planting. In micronutrient deficient soils, ZnSO4 @ 25kg/ha can be applied as
basal dose.
Irrigation
Irrigate immediately after planting and later at weekly intervals. Withhold the irrigation
ten days before harvest.
Disease
Diseases:
The occurrence of wilt is becoming a major problem in coleus cultivation. Pathogens associated with wilt and root rot are Fusarium chlamydosporum, Macrophomina phaseolina, Rhizoctonia solani and Sclerotium sp coupled with incidence of root knot nematode
Meloidogyne incognita. Due to these diseases, the yield loss is up to 50 to 60%.
Management Strategies for Disease
Select the coleus cuttings from disease free plants.
Coleus cuttings have to be treated with carbendazim solution (0.1%) before planting
Soil drenching with carbendazim (0.1%) or propiconazole (0.1%)
Soil application of FYM @ 12.5 ton/ha + 500 kg neem cake/ha + Trichoderma viride @ 2.5 kg /ha before planting is effective for bio management of nematode fungal disease complex involving Meloidogyne incognita and Macrophomina phaseolina
Application of chemical nematicide carbofuran 3G @ 1 kg a.i/ha before planting for control of root-knot nematode.
Use drip irrigation to minimize the spread of pathogens from infected plants to healthy plants
Harvest
Crop can be harvested six months after planting. Before harvest, top portion should
be removed when sufficient moisture is in the soil. Roots are dug manually or by tractor
drawn harvester. The soil particles are removed and the tubers are cut into small bits using
motorized chopper to facilitate drying. The cut root bits are dried under sun for 3-5 days with
frequent turnings until the moisture drops to 6-8 per cent.
Yield
Fresh root: 15 – 20t /ha , Dry root: 2 – 2.2 t /ha
