Three field trials were conducted from August to December 2007, October 2007 to January and February to April 2008 at the Vegetable Evaluation Research Station in Anse Boileau, Seychelles, to evaluate the efficacy of a botanical and a biological extract method for controlling the diamondback moth (Plutella xylostella L.) in cabbage (Brassica oleracea var capitata L.). Thuricide TM (Bacillus thuringiensis), garlic extract and the control set up were applied as treatments in a randomized complete block design. The treatments were replicated four times. The results showed significant differences between treatment plots where Thuricide TM was applied as compared to the other two treatments. The mean percentage of head damage in the first two trials for Thuricide treatments was significantly lower (9% 10%) compared to garlic extract (89% 90%) and the control (94% 98%). In the third trial, the non-treated plots obtained a maximum mean percentage of head damage of 92%, followed by 74% for garlic extract and 13% for Thuricide TM application. These results demonstrated that the Thuricide TM application is effective for controlling the diamondback moth pest on cabbage.