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Meet your conservatory plant pests

So picture the scene; it’s a hot summer’s day but luckily the drinks are cool and your finely tuned array of plants, flowers, fruit trees and shrubs are finally in full bloom. On closer inspection you find that the warmth of the conservatory has attracted an army of common enemies and these have taken up camp in the leaves and stems of your delightful plants! If only you had known your conservatory pests more, and done something about it!

It’s never too late

The most common conservatory pests are found feeding on the flowers, buds, leaves and stems. If they are not dealt with they will do irreparable damage to the plant. Some of the conservatories most damaging pests are:

greenfly-943285_640Aphids (greenfly & blackfly)

These crawling and winged bugs can be found in clusters, sucking the sap of new shoots and buds. Although the name suggests otherwise, they can also be yellow or brown in colour.  Once attacked, a plant’s leaves become sticky and fuliginous.


As with Aphids these tiny moth-like white insects suck the sap of plants and reduce the leaves to a sticky mess. Unlike Aphids however, these flying insects are discovered on the undersides of leaves.


Small oval soft-bodied insects who leave a cloud of white ‘cottonwool’ waxy residue on stems and leaves.

Red Spider Mites

Barely visible to the eye, these tiny red or yellow crawling dots are found on the undersides of leaves or as spun webs around the shoots.

Slugs, Snails and Caterpillars

As well as devouring leaves and flowers, slugs and snails leave slime trails and caterpillars constrict shoots by spinning webs around the tips.

Unfortunately the regular pesticide method of removing these predators isn’t possible inside a conservatory as there is a real danger of causing harm to pets and small children. So what can you do to keep conservatory pests to a minimum?

The biological principle

Although some pesticides are recommended to be used in the winter months, the ideal method of controlling pests in the conservatory is the biological principle. This method involves administering a predator of the pest (a ‘dog eat dog’ system) and for this to work effectively it’s vital to introduce the predator as soon as you spot the pests.

As Planet Natural tell us: “Beneficial insects feast on aphids, mites, caterpillars and other plant-consuming bugs and are harmless to people, plants and pets.”

Buying bugs to eliminate bugs may seem like a strange way to do things but time and time again, the experts agree that it undoubtedly works!

The method

On purchasing and applying the predator, it’s important to check regularly that they are doing their job. It may require several batches re-introduced over a period of time to get the ratio of numbers correct.

The following are the expert’s recommendations:

  • Aphidoletes aphidimyza (a midge with long legs which attack aphids)
  • Encarsia formosa (tiny black and yellow wasp which destroys the whitefly grub)
  • Cryptolaemus montrouzieri (an orange and black tropical ladybird that devours Mealybugs)
  • Phytoseiulus persimilis (these mites are visible as tiny pink or red shiny dots and can move faster than the Red Spider Mites, eating both adults and young)

Natural born killers

As well as the encouraged introduction of the predators it’s beneficial to allow other insects to come in from the garden and interact with the conservatory plants. The ones that should should be welcomed are:

  • Bees (vital for pollination)
  • Ladybirds, lacewings, hoverflies (they attack red spider mites and aphids)
  • Ground beetles, black beetles (they destroy slugs and snails)

Nobody wants their conservatory plants to be overrun with either good pests or bad, so many people still find that pesticide treatment is the only option. In a later post we shall take a look at the safer pesticides available. Rest assured it’s possible to enjoy your conservatory or orangery without having to put up with unwanted pests.