A small oval-shaped black or dark brown beetle, 3-4mm long, the hibiscus or sap beetle can be found on various flowers, including hibiscus, abutilons, dahlias and the weeds bindweed and morning glory. They tend to hide in the flowers’ buds, feeding predominantly on pollen and nectar, though they are known to chew holes in the petals too. Once the pollen has gone, the flower buds drop to the ground – a sign that your plant may have hibiscus beetle.
These beetles are hard to treat, as they are safely cocooned inside the flower buds. Any spray on the flowers will also affect other (beneficial) insects that seek out pollen. But there are a couple of tricks to keep them contained.
Each day, remove any dropped flower buds and dispose of them off of the property, as the beetles may still be inside.
Fill a couple of white or yellow containers with soapy water and place them at the bottom of the plant. The beetles are particularly attracted to paler coloured flowers and the pale-coloured water-filled containers may attract and drown the beetles.
A spray of neem on the soil surrounding the base of the plant may stop larvae from pupating in the soil.
Read our top tips for growing delicious and healthy passionfruit.Read More
Growing companion plants in and around your veggie garden is a great way to help keep your edible plants happy and healthy.Read More