This sounds like an attack of mealy bug! They are white, pale pink, yellow, grey or light brown coloured insects covered with a mealy, cottonwool-like substance. They thrive in warm, moist conditions and particularly in sheltered parts of a plant, like a leaf axil (where the leaf joins the stem) where they suck the sap.

What do do

They can be tricky to remove. Try washing them off with high-pressure misting water, or physically remove them using a cotton bud soaked in horticultural oil. Be very thorough, as a small amount left behind can re-infect again quickly. 

Keep a very close eye on the plant and check it every day (and other plants close by) over the next few weeks to ensure reinfestation hasn’t occurred. If you have further problems, spray with horticultural oil or neem oil - your local garden centre can guide you.

Boost Plant Health

Healthy plants can be less prone to pest and diseases. Feed with Garden Time Seafeed to help support the plant back to health. Regular fertilising and attention are also important to improve a plants vitality and health.