Ants have been farming on my herb plants.

For about 15 years, generations of ants have been successfully maintaining a helpful aphid population on herb plants, in a couple of my roof terrace pots. I grow Chamomile and Valerian in the pots which the ants prefer; they seem less impressed with the other herbs that I grow.

At first, I battled the aphids, rehoming Ladybird larvae to the aphid-struck plants (ladybird larvae feed ferociously well on aphids) because I feared that they would suck my Chamomile and Valerian lovelies dry. But now we’re freinds and here’s why: Because those aphids and their ant farmers keep the little ecosystem in the plant pots just right. Just right, because the aphids poke and suck the Camomile and Valerian just enough to stay alive themselves and keep their 6-legged offspring healthy, whilst provoking the herbs to produce high levels of phytochemicals in an attempt to keep the insect population manageable. The protective phytochemicals make the flowers even more medicinal for me too. Btw, plants which don’t have to work to survive become soft in my opinion and far less robust and medicinal than I’d like. The ants protect the aphids by keeping them nestled under the flowers, and away from me when I dare to handle the plants for too long. That’s the only time they nip me. I find them very relaxed otherwise. Ants like to keep themselves to themselves. So the ants give the aphids shelter and protection and stop them from over harvesting the plants. Not sure exactly how, I guess by eating them or killing some aphid larvae (need to study this further).

If the aphids overharvested the herb sap, their own population would explode temporarily but the host plants would then whither from too much sap removal, the aphids would need to fly elsewhere and the ants would not get their food. How unfortunate. And I wouldn’t get my Chamomile or Valerian harvest.

So what do the ants get out of all this? Well they sup on aphid honeydew, aka aphid excrement. Can’t get enough of it but actually they are quite restrained. Honeydew is sweet and tasty stuff (like me, you may occasionally enjoy it on Lime tree leaves) packed with plant sugars and no doubt also herbal wonderfulness, from the aphids’ diet. And what do the Chamomile and Valerian plants gain from all these shenanigans? Well they thrive well enough to produce thousands of seeds each summer; hundreds of which land in my other plant pots, dozens of which make it to becoming new plants – Plants which are tough, medicinal and can be friends with aphids, ants and me.

I guess that was a long way of saying, when you next see a cluster of aphids under a flower, along with an ant wandering over them, take a closer look. Maybe you’re lucky enough to have insect farmers working magic in your plant pots or garden. Please don’t just squish them away; watch what’s happening and perhaps you’ll have better herbs and a more balanced garden ecosystem by just letting them do their thing.

#urbanherbology #antfarmingaphids #urbanecosystems #urbanecosystem#mugwortandmarigold