A common problem on tropical plants. Although there are at least three species of Mealybug this predator deals with them all. Cryptolaemusmontrouzieri is an orange and black Australian Ladybird approximately 4mm long. In displays they should preferably be released late in the day at a rate of 2-3 per sq mtr.

For control of citrus mealybug (Planococcus citri). Leptomastix dactylopii is a 3mm yellow parasitic wasp that originated in Brazil but is now used worldwide. They attack large but immature mealybugs. Leptomastidea abnormis is a 1.5 mm long parasitic wasp, It attacks young 2nd instar stages of the Citrus mealybug and works under cooler conditions than the other parasitoids. Originates in southern Europe and has been used widely for biocontrol. Anagyrus pseudococci is a small parasitoid That prefers larger nearly full grown mealybugs but is able to develop in a variety of species. The citrus mealybug is the preferred host but it will also develop in the glasshouse mealybug (Pseudococcus viburni). This species develops faster than the other species. Originates from the Middle East but has become established as an effective biocontrol agent on most continents. Temperatures between 18 and 30C are required for development. Parasitised mealybugs continue to grow for a few days but then die and become brown and mummified. The parasite completes its growth inside this mummy. Available May to September only

This constant pest on Tropical plants is at it's worst during hot summer months. The webs used for travelling around the plants are easy to see, particularly around the leaf stems. Spider mite populations can reach enormous levels in a very short time. This predatory mite is an effective control. Predators are supplied in a shaker bottle mixed with vermiculite, which is shaken onto the infected plants. Low volume vermiculite shakers are supplied spreading rate 10-20 per sq mtr.

Areas of low humidity provide ideal breeding conditions for the spidermite but has the reverse effect on the predator Phytoseiulus persimilis. For these areas the predator Amblyseius californicus should be introduced. The terms of the licence state a maximum spreading rate of 2 per sq mtr. (Spidermite predators 1 & 2 can be used effectively together.

The tiny gall midge Feltiella acarisuga is an aggressive predator eating all stages of spidermites. The larvae can consume 30 spidermite or 80 mite eggs per day in dense infestations. The female lays around 100 eggs at a time around spidermite webs and colonies.

The first sign of a scale insect attack is usually the shiny deposits of the sticky honeydew they produce as they feed on the plants. They produce many hundreds of eggs, safely protected from chemical attack by their shell. Metaphycus helvolus is a small 1.5 mm long parasitoid that attacks soft scale insects particularly Saisettia coffeae and Coccus hesperidum the two most common pests on ornamental plants. The female lays up to 6 eggs per day one to each host with the preferred stage being young 2nd instar. However, it kills many more hosts by feeding on their blood. Three releases at fortnightly intervals at a rate of 5 per sq. mtr is most effective. Metaphycus helvolus was first collected in South Africa but has been widely used for biocontrol of soft scale.

Available May to September only

A black coloured parasitoid measuring about 2.5 mm in length that attacks soft scale such as Saisettia spp. The parasitoid chooses adult scales that are whitish in colour which turn blackish with the development of the grub inside.The generation time takes about 3-4 weeks at 25C. The parasitoid does best in warm conditions and each adult can lay around 30 or more eggs. This is a British species. Available May to September only

a mixture of predators 1,2 & 3 giving a wider range of control by combining their “hunting skills”. Available May to September only

A small black beetle that eats hard scale insects. Temperature must be above 22 0C and preferably above 25 0C for effective control. Egg production 3 eggs per day at 20C but 10 per day at 30C. Overall lifespan can extend up to 9 months and egg laying continues provided individuals are kept with a male and provided with adequate supplies of fresh food. Available May to September only

Glasshouse whitefly are not commonly found attacking plant displays but can be a problem while plants are in the greenhouse. The adult flies resemble small moths measuring 1.5mm and are found mostly on the underside of leaves and the growing tip of the plant, whilst larvae are to be found lower down. The parasitic wasp Encarsia formosa has been a recognised control of whitefly for some years. The Encarsia are supplied as small black pupae attached to cards designed to be suspended amongst the plants in the glasshouse. Spreading rate 2-9 per sq mtr.

The vine weevil (a medium sized wingless beetle) is now a common problem. The young grubs feed upon the roots of plants causing damage often leading to plant death. Larvanem is a preparation of insect parasitic nematodes which is mixed with water and then applied as a soil drench. The soil must be kept moist and during the treatment period the soil temperature should not fall below 14 o C, for heavy infestations repeat the treatment after 6 to 8 weeks.

The larvae of the sciarid fly (fungus gnat) feed on rotting plant material in the compost. These nematodes are mixed with water and applied as a soil drench.This should be used as a routine preventative treatment for sciarid and other soil borne pests. If adult sciarid flies are present it may take two weeks for a noticeable reduction.

These are supplied as adult mites bottled with inert carrying material. The adults and nymphs attack eggs, larvae and pupae preferring the smaller larvae. Also effective against shore-flies (Ephydridae)

Thrips, sometimes called "thunderbugs" feed by cutting slits in the plant tissue and sucking the exuding sap. Amblyseius are very active mites and both young and adult consume the young thrip. This predator is supplied in a handy bottle containing 25.000 predators in a bran which can be shaken onto the infested plants, or in sachets containing 500 predators which can be suspended from larger plants (Ficus trees, Palms, etc.) or throughout the glasshouse.