Just like humans, plants need water to survive. But how can plants "drink" water?
The process by which plants absorb water (and nutrients dissolved in it) from the soil via the roots is called osmosis. When transported against gravity from bottom to top, the evaporation of water on the leaves in the upper part of the plant acts like a suction. This pulls the water out of the soil through the plant upwards. With the help of these forces, trees can grow up to 130 metres high, for example.
You can make the water absorption of the plant visible by using coloured water.