Bananas that are planted out of doors in Great Britain are almost problem free with regards diseases and pests. However, unfortunately, when grown in a greenhouse or conservatory, red spider mite is a common problem which can easily take hold. Regularly spraying the undersides of the leaves with tepid water is a good preventative measure. If infestations by mealy bug take place in the roots and compost, cleanse all the compost away from the plants root system under a tap (use tepid water), and then repot the plant again in new compost and having reduced the plant’s leaf area.