Q: I bought a half-barrel to use as a planter, but it doesn’t have drainage holes. Do I need holes in the pot, or can I just add some gravel to the bottom for drainage? A: If you think you might use the pot for some other purpose in the future that will need to hold water, I would not add the holes. Otherwise, you should definitely drill the holes. Gravel in the bottom of a pot does not help the drainage. In fact, if you’re planting in clay soil in the landscape, adding gravel to the bottom of the pot or hole actually worsens the situation. Water moves through the soil in large and small pores. Large ones, such as those made by worms, can move water quickly, and they allow air to move in the soil, too. Small pores can be microscopic in size, and they allow water …