= Solution
A <hydrophobic> surface is poorly wetted by <water>: on a smooth surface its equilibrium <contact angle>, measured through the liquid, exceeds $90^\circ$. A drop therefore tends to bead up, limiting its contact area. Hydrophobicity does not mean that the surface exerts a mysterious repulsive force on every water <molecule>.
The waxy coating has a largely nonpolar exterior. <Water> <molecules> form favorable <hydrogen bonds> with one another, whereas a hydrocarbon-rich wax surface offers few suitable <hydrogen bond donors> or <hydrogen bond acceptors>. Water–surface adhesion is weak relative to water's cohesion. The drop shape minimizes the combined solid–air, solid–water and water–air interfacial <free energies>, not merely the liquid's exposed area.
In terms of <Young's equation>, $\gamma_{SV}-\gamma_{SL}=\gamma_{LV}\cos\theta$. A <contact angle> greater than $90^\circ$ corresponds to $\gamma_{SL}>\gamma_{SV}$: replacing dry surface by wetted surface has an interfacial cost. The balancing liquid interface then favors a small wetted patch. Microscopic leaf texture can amplify the apparent <hydrophobicity>, especially when it traps air under the drop as a <Cassie–Baxter state>; the chemistry of a smooth wax layer alone does not guarantee an extremely large apparent angle.
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