August Gardenias have a moderate growing rate, meaning they add about 1 to 2 feet of growth each year. When growing from seed, gardenias take about 2 to 3 years to begin flowering. When they do bloom, they will bloom for up to 3 months at a time. Your beautifully fragrant plant's blossoms span 2 to 3 inches across and their foliage can be between 1 to 1 1/2 inches wide. As long as you are taking care of your plant as recommended, it will grow consistently and beautifully for years to come.