Natural Pesticide from Pongamia Pinnata (Honge or Karanj) Seed

In Karnataka it is known as the Honge (hong-ay) tree. In Hindi  (or Bengali) it is called Karanj. In English it is known as the Avenue Tree. Its botanical name is Pongamia Pinnata. The tree and its seeds are shown to the left here. A close-up of its leaves and flowers are shown below.

Honge or Karanj Leaves and Flowers

This tree is commonly found all over India, particularly along the streets in rural Karnataka, and I have spotted several of them along Bannerghatta road, in Bangalore. It is a lovely tree that springs fresh light green leaves in abundance in Summer when its shade would be most useful to humans and animals.

The seeds of this tree fall to the ground and can be easily picked up and stored for future use in oil extraction or for making home-made natural pesticide.

Karanj Cake

The seeds could be taken to a crushing mill, where they would extract the oil from the seed. This oil could be used for lighting a lamp at home, or as a fuel (commonly referred to as Bio-diesel) for running water pumps. It can also be used (directly without any modification to the existing engine) in vehicles that run on diesel, by adding a small portion of it to the diesel in the fuel tank. Part of it burns with the diesel, and part of the oil serves as a good lubricant for the engine.
The oil and its cake (what remains after oil is extracted) are shown above.

To make natural pesticide, crush one kilogram of the seed lightly with a stone on a flat surface, striking lightly such that the seeds are broken into bits without its oil being crushed out.

Collect the above crushed seeds in a soft cotton cloth (an old piece of dhoti or towel), and tie the cloth into a knot so that the crushed seeds are tightly packed within. Soak this pack in a bucket with four liters of fresh water for twelve hours.

After soaking for twelve hours, squeeze the cloth pack while it is in the water to extract the white solution that has formed in the pack. After about five minutes of squeezing the water in the bucket will look milky. Remove the squeezed cloth pack out of the milky water, and keep it aside.

Pour all the four liters of the milky solution from the bucket into a spray pump that has a tank capacity of 16 liters. Fill up the tank by adding fresh water (about 12 liters). Shake the tank well to ensure the water and the white solution are mixed well, and use the hand-pump to spray this mixture on to plants, and their leaves. This serves as a zero cost, easily available, natural pesticide. Spraying may be done every fortnightly (once in two weeks).

This Honge seed extract is effective against Bacillus Anthracis, Bacillus Mycoides, Bacillus Pulilus, Escherichia Coli, Pseudomonas Mangiferae, Salmonella Typhi, Sarcina Lutea, Staphylococcus Albus, Staphylococcus Aureus and Xanthomonas Campestris. At the same time it does not leave any chemical residue in the soil, is perfectly eco-friendly, natural and virtually free of cost.

What remains in the cloth pack could be used as fertilizer, as Karanj or Honge Cake is known to be rich in N-P-K.