This study explored the influence of N-(2-chloro-4-pyridyl)-N-phenylurea (CPPU) treatment of the roots on shoot growth and root growth, and investigated the effects of a GA3 foliar spray on reversing the growth suppression of chilli ‘Ancho St Luis’ shoots due to CPPU treatment of the root system. In the first experiment, six-week-old chilli seedling roots were soaked in an aqueous solution of CPPU (10 mg？L-1) for two hours, transplanted into pots and grown in a glasshouse. In the second experiment, the roots of six-week-old seedlings were soaked in three concentrations (1, 5, or 10 mg？L-1) of CPPU for two hours, transplanted into pots, and grown in a glasshouse. Four weeks after CPPU treatment, the plants were sprayed with gibberellic acid (GA3) at 100 mg？L-1 as a single foliar spray. Results showed that root applied CPPU at 10 mg？L-1 significantly decreased plant height, probably by inhibiting the activity of the sub-apical region of shoot, reducing internode number and length at 2 an