Raising Seedlings in Container
Leaf cups, thin container, earthen pots, polyethylene bags of medium size are prepared from 200-300 gauge thickness are used for raising the seedlings. At the bottom of the bags drainage holes are prepared. The size of bag may be depending upon the period of seedlings to be maintained in the Nursery, e.g. seedlings are raised till first year then large bags are needed. Bags should be filled with potting mixture containing fine fertile soil and compost in 3:1 proportion. If the soil is sticky then to increase the porosity of soil one part of sand is also added to the moisture. Small quantity of carbaryl powder is added to get rid of termites and ants. While filling the bags 1.5 to 2 cm of mouth side should be left for irrigation water. 2-3 seedlings are sown in each bag. The bags are placed in line and watered regularly.
Time of Sowing: Time of sowing can also be adjusted according to time of planting. It also depends upon time of seed maturity and seed viability. This will avoid excessive cost of maintenance of the seedlings. Subabhul 8-10 month old, 1 m height are used for planting.
Time of sowing can also be adjusted according to growth of seedlings e.g. fast growing species like Acacia, Casuarina can be sown late whereas slow growing species like sandalwood require early sowing to attain proper height or growth at the time of planting. To avoid rise of damage of seeds due to natural hazards like change in climate conditions (adverse), heavy rains, extremely low temperatures, high temperature, so all seeds are sown in 2-3 lots at an interval of 10-15 days. The seeds are sown on the onset of monsoon. Some seeds require pre-sowing treatment for better germination.
Care Taken for Containerized Seedlings:
In addition to watering, shading, shelter, seedlings nutrition and weed control, the container raised plants require to be shifted in the new beds after every two to three months to avoid penetration of deep tap root system in to soil. The black polyethylene film is used below the polyethylene bags and, the bags are arranged in sunken nursery beds obtained by 10 m size in rows of 10 in number which accommodate about 1000 plastic bags. The polyethylene bags are changed to larger size and the plant are transplanted into new bags this is done in case of the road avenue plants and other seedlings which are require two to three years and 1 to 1.5m in height for example Eucalyptus is sown in 20 x 10 cm bags and are seedlings transplanted after 3-4 months in 40 x 20 cm polyethylene bag and shifted to new place after every 1 or 2 months. The hardening of seedlings is done before the seedlings are planted in field. Hardening is the operation of reducing amount of irrigation water 10-1-5 days prior of planting out. This operation is necessary to make the seedlings physiologically fit to thrive over transplanting shock, adverse climate condition in the field. It is helpful to reduce the