i would spray with rose clear.you can get it from any garden center.its normally for roses but you can use it on any plant .it contains 3 ingredients.1 a systemic insecticide...absorbed into plant leaves and stem to prevent insect attack.2 also acts as a fungaside to combat any fungus attacking the leaves and 3 prevents further attacks.simply put ...the insects wont touch the leaves of the plant .works for me. dont use it when its sunny, use on a rainy day in the greenhouse early in the morning to give it a chance to dry before night.