How to Water Flower Boxes
- 1). Test your window boxes before you plant them to make sure the holes are not blocked and water can drain freely. Most annuals, especially begonias, will die quickly if left in soggy soil. Mix two parts potting soil with one part vermiculite to get a mix that will drain but also hold a little moisture back on extremely dry days.
- 2). Set a schedule and stick to it. If your window boxes get full sun, water every other day if it doesn't rain. If window boxes are under an eave, water every other day whether it rains or not. If your boxes are full of lobelia, water every day; these plants will crisp up quickly in full sun if you don't. Window boxes that get light shade can be watered every three days.
- 3). Do all your watering in the early evening, when the heat of the day has passed, to decrease evaporation. Use a small watering can to reach roots under spreading leaves in the window box. Water until you see water drip from the drainage holes.
- 4). Use a garden hose with a spray attachment to deliver a quick soak and spray to the leaves and flowers in the window box. Climb a small stepladder to deliver water down into the box, rather than up at it.
- 5). Water second-floor window boxes by opening windows and screens and watering from inside. Again, keep watering until water drains freely from the bottom of the box.
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