Abstract: The variations in the yield and composition of the essential oils from Calendula officinalis L. (Asteraceae) cultivated in Alice, Eastern Cape of South Africa are reported. Essential oils of this plant were obtained by hydrodistillation using the Clevenger apparatus and analysis was performed by GC-MS. The yield in essential oil showed a maximum at the full flowering stage (0.97%) and a minimum during the pre-flowering stage (0.13%). The compositions also showed different patterns at different phases of the vegetative cycle. Sesquiterpenes (α-cadinene, α-cadinol, T-muurolol and epi-bicyclosesquiphellandrene) and monoterpenes (limonene, 1, 8-cineole and trans-β-ocimene) showed the highest correlations with the age of the plant. Aiming the use of essential oil as a food ingredient, the most interesting stage is the post-flowering period, the essential oil at this time being rich in α-cadinene, α-cadinol, t-muurolol, limonene, 1,8-cineole, with P-cymene present at lower levels. α-cadinene is an important flavouring agent in baked foods, candy and chewing gum and also used as a fragrance in cosmetics and detergents. T-muurolol and α-cadinol are important antimicrobial agents.