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Long before it was bottled for soap makers, neem oil was burned for light. Across its home range it was, and in places still is, the everyday lamp oil: pressed in the village, poured into a clay diya with a cotton wick, and lit at dusk. It is the oldest use of the oil there is, and it still works.
In a clay lamp
Neem burns neat in a shallow open lamp. Warm the oil until it pours, fill the bowl, lay a twisted cotton wick with a centimetre showing, and let it soak for a few minutes before lighting. The flame is soft and yellow and the oil burns slowly; a tablespoon lasts an hour or more. Expect the neem smell while it burns, warmer and less sharp than the cold oil.
In a wick lantern
Neem is too thick on its own for a lantern with a long wick; it will not climb. Blend one part neem with three or four parts of a purpose-made lamp oil for a brighter, steadier flame that still carries the scent.
In a garden candle
Neem is not a wax, but a little stirred into melted soy or rapeseed wax, under 5 per cent of the wax weight, softens the set and carries the earthy scent through the burn. Test the wick size; added oil changes the melt pool. Container candles in tins suit an outdoor table.
Notes
- An open flame needs watching; keep lamps on a stone or metal base and away from anything that can catch.
- Neem sets solid below about 20 °C; a lamp filled on a cold evening may need the oil warmed first.
- Soot means the wick is too long; trim it.
Other things to make with the oil: what is neem oil used for?