No, hydrophobic does not refer to an unreasonable fear of water.
Instead, hydrophobic describes the point where soil becomes so dry that it actually repels water (read: bad for your plants). Much like a dried out sponge, when water is applied to overly dry soil, the water simply runs off and is lost.
If your plants become hydrophobic, simply pouring water on them is not enough. Instead, you can revive your plants and thoroughly hydrate the soil by forcibly submerging the pot in a bucket of water until the pot no longer floats. Until the soil is saturated with water, the air pockets in the soil will make the pot float. It's pretty cool, watching all the air bubbles percolate up from your submerged pot!
Another method of rehydrating hydrophobic soil is to place the pot in a large container and pour water over the top. The water will run out of the soil but, over time, the water will eventually be absorbed and your plant will thank you!
You can grow a surprising amount of food in your own yard. Ask me how!