This is a good practice because the compost will gradually feed the plants as they are watered. Constant watering washes out nutrients, which must be replaced. Watering Containers Instead of putting a matching saucer under an outdoor container, turn the saucer upside down to lift the pot off the ground and help drainage. Excess water can cause plant roots to rot. Some companies make cute little clay feet to rest your container on.
Bricks work well, too.
Smaller containers dry out much faster than larger ones. When it's very hot, even large containers require daily watering, but small ones might need it even more often. Water-holding crystals that swell with moisture and feed it slowly to plant roots can be mixed into the planting medium when potting. They also can hold too much water during a rainy spell. Don't use them in pots with more drought-tolerant plants such as succulents.