About 6 weeks ago I bought a new scented leaved pelargonium. I like to keep these in pots near to the house so that I can touch the leaves as I pass and enjoy the different scents. This particular variety has an open habit with beautiful, quite large bright pink flowers with white throats and so I left it in its plastic pot and put it in another more decorative one and placed it on an outside window ledge in order to enjoy the sight of the flowers from within the house too. Yesterday morning I watered it early, as usual, but later in the afternoon when walking outside past the low window where it is sighted I registered out of the corner of my eye that the window sill, pale terra cotta tiles, had turned dark brown. A closer inspection revealed that it was covered with fine, dry compost......and ants. I lifted the plant from the pot, my arms getting covered with ants in the process, and saw that the roots and the little remaining compost was a mass of tunnels where the ants had been busy building up their colony. Obviously space was getting low and the time had come to emerge into the wider world for many of them. I dunked the plant into a bucket of water and set about de-anting myself and sweeping up the compost from the sill and path below. Luckily none of the ants had found their way into the house through the window.
This plant had not appeared to have been suffering despite the activity around its roots but from now on I shall be more aware that ants could be causing problems when plants in pots fail to thrive.
