Preparation of Neem Based Extracts

Preparation of extracts

Neem Kernel Extract

Fifty grams of neem kernel are required for use in 1 litre of water. The neem kernel is pounded gently in such a way that no oil comes out. The outer coat is removed before pounding. This is used as manure. If pounded with the seed coat on, one and a half times the amount of seeds (75 g) is required. The seeds that are used for the preparation of neem kernel extract should be between three and eight months old. Otherwise, the quantity of azadirachtin in the seeds is quite low and hence they cannot be efficiently used for pest control. The pounded neem kernel powder is gathered in a muslin pouch and soaked overnight in water. The pouch is squeezed and the extract is filtered. To the filtrate, an emulsifier like khadi soap solution (a soap with no detergent) is added. One millilitre of emulsifier is added to I litre of water. The emulsifier helps the extract to stick well to the leaf surface.

Neem Leaf Extract

For 5 litres of water, 1 kg of green neem leaf is required. Since the quantity of leaves required for the preparation of this extract is quite high (nearly 80 kg are required for 1 hectare), this can be used for nursery and kitchen gardens. The leaves are soaked overnight in water. The next day, they are ground and the extract is filtered. The extract is suited for use against leafeating caterpillars, grubs, locusts and grasshoppers. To the extract, emulsifier is also added.

Neem Cake Extract

A hundred grams of neem cake are required for 1 litre of water. The neem cake is put in a muslin pouch and soaked in water overnight. It is then filtered and an emulsifier is added at the rate of 1 millilitre for 1 litre of water, after which it is ready for spraying.

Neem Oil Spray

Thirty millilitres of neem oil are added to the emulsifier and stirred well to ensure that the oil and water can mix well. After this, 1 litre of water is added and stirred well. It is very essential to add the emulsifier with the oil before adding water. It should be used immediately, otherwise oil droplets will start floating. A knapsack sprayer is better for neem oil spraying than a hand sprayer.

Pongam, Aloe and Neem Extract

One kilogram of pounded pongam cake, 1 kg of pounded neem cake and 250 g of pounded poison nut tree seeds are put in a muslin pouch and soaked overnight in water. In the morning, the pouch is squeezed and the extract is taken out. This is mixed with 1/2 litre of aloe Vera leaf juice. To this, 15 litres of water are added. This is again mixed with 2-3 litres of cow’s urine. Before spraying, 1 litre of this mixture is diluted with 10 litres of water. For an acre, 60-100 litres of spray are used. This is effective in the control of pests of cotton and crossandra.

Custard apple, Neem, Chilli Extract

Five hundred millilitres of water are added to 2 kg of ground custard apple leaves and stirred. This is filtered to get the extract and the filtrate is kept aside. Separately, 500 g of dry fruits of chilli are soaked in water overnight. The next day, this is ground and the solution filtered to get the extract. One kilogram of crushed neem fruits is soaked in 2 litres of water overnight and the extract is filtered. All the three filtrates are subsequently mixed with 50-60 litres of water, filtered again and sprayed over the crops.

Note:  For all the above extracts, 250 millilitres of khadi soap solution

should be added as an emulsifier before spraying.

General remarks about spraying

(a) Spraying should be undertaken in the morning or late in the evening. Under hot conditions, the frequency of spraying should be increased. In winter, spraying once in 10 days and every day in the rainy season is recommended.

(b) Insects lay eggs on the underside of the leaves. Hence it is important to spray under the leaves also.

(c) While using a power sprayer, the quantity of water used should be halved.

(d) It is better to use low concentrations of extracts frequently.

(e) As a general guideline, it can be said that each acre of land to be protected can be sprayed with 60 litres of ready-to-use solution (not the concentrate). Of course, the volume may have to be varied depending on the exact conditions prevailing, such as the intensity of the pest attack.