A water garden could hardly be called a garden if it is without plants. Water garden plants could easily be categorized into three main types:
1. Submerged, in which plants are completely inside the water. These planted in ponds are called oxygenators. The examples are hardy waterlillies.
2. The next category includes marginal plants whose roots are inside but top is floating on the water, like water lettuce, lotus, elephant ears etc.
3. The last one includes floating plants not at all touching the soil. This includes water lettuce, water hyacinth etc.
On occasions, these water plants could be one reason for establishing these water gardens.