Aphids

Almost all gardeners will know what aphids look like, whether they are black, green or white. We don’t discriminate here – they are equally horrid. Winged aphids are small enough that they can drift around on currents of air during the warmer months in Britain and they easily waft in through open doors and windows. They can sneak in with vegetables, flowers, on your clothes or via infected plants. They aren’t a major pest on orchids, mainly latching onto developing new growths or sappy flower spikes where they are easily squished. Still, they can be quite disfiguring on open flowers where they seem able to absorb the pigment from whatever they are feeding on to camouflage themselves. If you keep plants outside during summer (particularly Cymbidium, some Dendrobium and some Coelogyne), you may well pick up an infestation then, and they in turn attract ants which farm them. Indoor growers generally don’t have issues with them. They can be prevented access with cleanliness and by putting fine net curtains up against your windows, and mosquito netting works very well across growroom doors.