Two Sundays ago, the National Agricultural Research and Extension Institute (NAREI) started a series on coconut production to share pertinent information with coconut farmers and persons interested in joining the industry. This week NAREI is sharing information on the maintenance of pre-nursery seedbeds and main nursery beds.

Irrigation: After sowing, the seednuts should be irrigated thoroughly to saturation levels. The seedbeds should be irrigated regularly to ensure that the soil is moist. Regular application of water is compulsory under dry weather conditions. Keep seednuts cool by sprinkling water on the nuts as required, to avoid drying out of water in the endosperm. This can be done using overhead sprinklers or a garden hose fitted with a nozzle.
In the pre-nursery beds, apply 0.5 liter water to each sprouted seedling at least once every three to four days depending on weather conditions. In the nursery bed, apply one liter of water to each seedling every two days if there is no rain.

Weed Management: Weeding helps in moisture conservation of the seedbed and should be conducted manually by hand-pulling once or twice per month or with a wick wiper containing a systemic herbicide.

Fertilizer application: Chemical fertilizers need not be applied to the seedlings in the pre-nursery during the first two months after sowing since the seedlings are usually nourished by the endosperm. Thereafter, a blend of fertilizers can be prepared by mixing one unit urea with two units TSP and four units KCl. The blend should be applied at a rate of 30 g/plant at two months after germination and at 60 g/plant at the 4th and 6th months. From the two-month stage and onwards, a solution of MgS0₄ should be applied monthly at a rate of 10 ml per 4.5 liters water.

Mulching: During hot, dry periods, pre-nursery and main nursery beds can be covered with 65% shade cloth, mounted on posts 2m high. The surface of the bed can be mulched with dry fronds and/or coir. This can promote early and more efficient germination, good seedling growth and better establishment.

Pest and disease management in the nursery
Careful inspections should be made regularly to detect incidence of pest and diseases in the nursery. Scales, whiteflies and mealy bugs are often found on the underside of the leaves. Dimethoate sprayed at 0.05% and a spreader sticker can be alternated with Triazophos 40% EC to keep these pests at a manageable level. The biological insecticide, Bioneem or Neemex can be sprayed with a sticker onto the under surface of the leaves to control mites. For leaf spot and bud rot diseases, preventative treatments of 1% Bordeaux fungicide alternated with 0.3% Idofil M-45 should applied twice per month. Severely infected leaves should be removed and burnt.

Seedling Selection
After four to five months in the main nursery bed seedlings could be selected for transplanting to the field. Importantly, transplanting seedlings into the field should coincide with the onset of rains. Proper selection of seedlings in the main nursery alone ensures a 10% improvement in yield.
The following considerations should be made when selecting seedlings for transplanting to the field:

• Shoots should have a girth of 10 – 12 cm at the collar.
• There should be a minimum of six leaves with youngest already differentiated into leaflets.
• The leaf stalks should be short and thick.
• Seedlings should have a robust healthy appearance and free from pests and diseases.
• If rigorous standards of selection are adopted, 60 – 65% high quality seedlings in a nursery can be obtained from the total nuts sown.

Seedlings that do not meet these criteria should be rejected.