Things to do this week:
* Water Gardens. Aquatic plants such as waterlily and lotus grow only when the weather really warms, so now is the time to buy them and put them in a pond or pot.
Many will grow wonderfully in water-filled containers that are only 15 to 18 inches deep and as wide or wider. The new generation of thick, sturdy plastic pots--often made from recycled materials--make great free-standing water gardens if you don't open up the drainage holes (or if you stopper existing holes).
There's no need to circulate or filter water, but keep 75% of the surface covered with plants to prevent algae and be sure to include common feeder goldfish to deter mosquito breeding.
No room for lilies and the like? Grow things such as the weedy but wonderful floating water hyacinth in smaller containers. Tiny floating ferns will even fit in a small ceramic bowl filled with water. A friend used to keep one of these in the center of her patio table, to cooling effect.
* Water Wisdom. Learn to tell the difference between the temporary wilting of plants on really hot days and those times when they really need irrigation. On ultra-hot days, plants simply can't take up moisture fast enough and no amount of watering is going to help (and might, in fact, hurt). The only way to really tell when a plant needs water is to plunge something--say, a spade or even a screwdriver--into the ground to see if the soil is moist. It's OK, however, to cool the foliage by lightly spritzing plants on really hot afternoons.