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Ants & Aphids

Ants farming aphids

An ant farming aphids.

Orchid growers, particularly those that grow in a greenhouse or any space that is close to the outdoors, need to keep an eye out for ants. Ants in themselves pose little to no harm to orchids but if you see them in numbers you might be witnessing an ant farm – a literal farm, that is. Ants are incredible creatures and one thing they have learned how to do is farm aphids. Ants will propagate aphid larvae in order to keep a steady supply of aphids to eat. Aphids suck on plants (and LOVE orchids) eventually killing them. Fortunately aphids are easy to kill but if you’ve got a large team of ants fighting against your aphid-killing efforts you may have a problem on your hands. Without the help of ants, orchids that grow outdoors can easily succumb to aphid infestation and need to be checked regularly and sprayed if aphids are found.

If you have a problem with ants and aphids you need to take care of both pests. This is a problem that typically affects greenhouse growers, but it can be something indoor growers could see.

Issue Treatment Details Indoors?
Aphids Insecticidal Soap Basic insecticidal soap should rid you of aphids. Make sure that the soap says it kills aphids and can be used on orchids. If it doesn’t indicate that it can be used specifically on orchids, see if it says “ornamentals” or African violets. If so, it will probably be ok on your orchids. Repeated treatments might be wise but if your aphids are living in conjunction with ants you should expect to see more aphids in the future – so keep that soap ready! Safe indoors.
Ants (numerous treatments) Ants don’t really harm orchids, but they do farm aphids, so their presence in any number, especially when coupled with aphids, is a bad sign. Ants will not respond to most treatments that orchidists have on hand for killing pests. Utilize an ant killing solution that can be used outdoors as it will be getting wet along with your orchids (there are many options at garden stores). Keep an eye on the ant population and continue to treat for aphids while you are dealing with the ants.Find the source of the ant infestation. If they’re coming from outside, plug whatever hole or crack they’re using to get in. Powder ant killers are effective for killing or detering ants, but they are very toxic and you may want to avoid them – especially if you have pets. Depending on the treatment this should be used with caution (especially around pets)