The tropical plant Pandanus, or screw pine, is said to repel cockroaches and other insects. More than 600 species of Pandanus exist in tropical areas, including the Pacific islands and Australia. The leaves are also used in cooking.

...
Fresh pandan leaves are said to repel cockroaches.

Identification

The various Pandanus species are sometimes called palms, although they are not related. Pandanus trees are large shrubs or small trees with a broad canopy and large fruits that resemble pineapples. Branches are long and sport palm-like foliage in clumps at their tips. Many species have large above-ground prop roots that help support the tree.

Use as a Cockroach Killer

If you place several 2-inch lengths of fresh Pandan leaves in a basket, it might repel or kill cockroaches that venture near them. When you no longer smell the fragrance of the cut leaves, replace them with fresh leaves to ensure continuing control of cockroaches and other insects.

Other Uses of Pandan

The Pandanus tree is a hardy plant that thrives in coastal areas of the tropics. It serves as a carefree landscape plant that requires little water or fertilizer. In countries such as Thailand, Vietnam, Malaysia and Indonesia, it is cultivated for use in cooking.