Non Flower Plants Respond To being Stressed.
Many plants that are not flowering such as Camellia and wisteria plants often start to flower after being stressed for example on non flowering wisteria we often suggest cutting with a budding knife the stem three quarters of the way around to a depth of 5mm to cut off some of the water and nutrient supply to the top and side shoots.The plant normally flowers as a result of stress producing flowers and seeds in response to a need to survive.
With non flowering plants its also a common mistake to start to feed them as this creates a situation were the plant does not feel the need to start flowering and producing seed.