The last time we went on a walking holiday we visited the Dolomites, where almost every house has a window box at every window, filled to overflowing with brightly coloured geraniums. They are all in peak condition, even though the summer is short in that part of the world. It is almost as if someone passed a law that made it compulsory to decorate the outside of your house with window boxes. The other thing that fascinated me was how they all managed to keep them in tip top condition all the time. Then, one day the weather changed and I discovered the secret - when it rains, each house has a set of covers for their garden window boxes. These consist of a long polythene cover with two rods to keep it steady. This just flips over the flowers and protects them from rain without resting on the blooms. Like all the best ideas, it is brilliant but simple.