By midmorning the sill had gone unusually quiet. The cactus was counting dust in a sunbeam, tapping a spine for each mote as if the light were a ledger. The geranium leaned in whenever the total drifted, murmuring a smaller number until both plants agreed.
We asked at the flower kiosk, where the seller was wiping a watering can. "They are not arguing," she said. "They are measuring how much warmth the afternoon still owes the kettle. If you hear a tiny correction, wait. Tea tastes kinder when the sill has finished its sums."
The next day a neighbor came back with a second cup, just to hear the count again. By then both plants already knew how much heat would do for one sip, and the teapot nodded first, then poured.