Water uptake by plants is through the roots. The root hairs provide a large surface area for the absorption of water. In flowering plants the water is pulled up the xylem through the stem and to the leaves.Transpiration is the evaporation of water from the leaves. This pulls water up through the xylem in a continuous stream due to the cohesion of the water molecules.The evaporation of water from the leaves is a passive process. The energy is provided by the Sun.