Above all, container gardens need consistent watering. Water slowly and thoroughly, until water drips from the pot's drainage holes. If possible, place the container inside a larger pot or washtub and soak it. To slow the drying process, position containers out of the afternoon sun. In hot, dry conditions, pots may need watering twice a day.
After plants have settled in for two to three months, apply a liquid fertilizer weekly, as directed. "Too much fertilizer will fry a plant's roots in a flash," says Roger. "Almost as fast as forgetting to water them."
This trio of terra-cotta boxes overflows with candytuft and marigolds