Niger seed comes from a plant called Guizotia abyssinica which is an annual herb grown not only for its seed but its edible oil too. It was cultivated in Ethiopia but is now found growing in other parts of Africa and India. The seed is technically a fruit known as a achene and it is often sold as bird seed.
Niger seed is also known by a variety of different names including nyger, ramtil, inga and black seed. It is also sometimes referred to as thistle seed but this is incorrect as the plant is not a thistle. The name occurred due to early marketing of the seed to take advantage of finches' natural love of teasel and thistle seeds which niger is similar too.
Niger seed has been used for many years in North America as a bird food, particularly for gold finches. It is rich in oils and other nutrients essential for birds and is high in calories. By putting out niger seed you will attract a wide variety of birds to your garden.
Niger is a lot finer than other types of bird seed so you will need a special niger feeder which is usually made of mesh to hold the seed. Buy one with a number of perches on it and if you're lucky you will see a whole flock of finches at it.
When putting out niger seed or any bird food make sure it is available at peak feeding time such as dawn and dusk. Keep all bird feeders away from predators such as cats and make sure the feeding stations are kept clean to prevent the spread of disease. Store all bird seed in a cool, dry place and ensure that you use it up before the sell-by date.
Niger seed can be quite expensive as it is imported and must also be sterilized to prevent the seed being introduced as an invasive species. As well as being used to feed birds, niger seeds are used in southern India to make a dry chutney or as a spice in some curries.
You can find out more about niger seed at British Bird Lovers.