The Cayman Islands is known for its lush landscapes and beautiful gardens, but these tropical spaces can also attract unwanted pests.
Giles Smith, founder of Paradise Landscaping, offers professional advice on how to spot and treat these uninvited guests and guard against infestation.
Whiteflies:
As the name suggests, they are small, white, flying pests (although not in the fly family) and they feed on the leaves of plants. Whiteflies generally live on the underside of the plant leaves and cause damage to plants by feeding on the sap from inside leaf tissue. Heavy infestation can cause significant leaf drop and stress to the affected plant(s).
Chemical and organic control options are readily available but complete spray coverage of the entire plant, and primarily the underside of the leaf, is required.
Chemical options: Imidichloprid, bifenthrin, caprid.
Organic options: Neem oil, insecticidal soap, horticultural oil. A follow-up application in 7 to 10 days is generally required to target the eggs that can hatch after the initial spray application.
Scales:
Insect scales fall into two groups: soft bodied and armoured. Scales are a sap sucking pest and feed on the leaves, stems and shoots of many plant species. Heavy infestation can cause branch dieback and even kill smaller or significantly stressed plants. A common tell-tale sign of a heavy scale infestation is the presence of ‘black sooty mould’ or ‘black lice’ (as more commonly called here in the Cayman Islands) on the host plant or on the understorey plants and surrounding hardscape. This is the result of the feeding activity of the scales and the resulting ‘honey dew’ that is excreted from the scales.
‘Honey dew’ is a sticky, sugary substance that supports the growth
of the black fungus ‘black lice’. Chemical and organic options
are available but ‘systemic’ chemical controls work better on the
armoured scales.
Chemical options: Imidichloprid, caprid and acephate.
Organic spray options: Neem oil, insecticidal soap, horticultural oil.
Spider mites:
Spider mites are tiny sap-sucking pests with some species resembling spiders, the most noticeable resemblance being the silk webs that they produce. While spider mites can be very hard for some to see with the naked eye, a severe infestation can be evident from the ‘scorched’ and desiccated-looking leaves of the host plant. A closer look will show the webs along with the tiny spider mites busily moving around. Spider mites can cause severe damage and sometimes plant death in short order, if not treated.
Common host plants in Cayman are crinum lilies (all varieties are susceptible but the yellow and purple varieties seem to be a favourite) and several species of palms. Spider mites can be difficult to control with conventional insecticides. The best control is achieved with the use of ‘miticides’, or a combination of both.
Chemical options: Abamectin and bifenthrin.
Organic options: Cure and neem oil.
This article appears in the Autumn/Winter 2023 issue of InsideOut magazine, now available at magazine stands around the island.
