For the last week I’ve fielded a few questions about the clawfoot tub from my previous post, so I thought I would share the process of how I repurposed mine into an outdoor planter — though there wasn’t much to it.
The tub was already in the yard when I moved into my house. It was propped up on a pile of stones under the partial shade of a mature feijoa tree, and as you can see, it sits slightly askew to promote drainage through the original drain hole. Unless you knew about the tilt, you wouldn’t notice it just walking by the tub.
In a climate like Southern California, which gets little rain, drainage isn’t a concern for me. (Though we did receive several inches in our recent set of storms, and the tub held up well with no waterlogging.) If you live in a very rainy climate, it might be a wise idea to drill a few more holes in the bottom to help with root aeration.
I don’t recommend adding stones, styrofoam, pot shards, or any of the other fillers people often turn to for pot drainage. This is a long-standing gardening myth that refuses to die, despite simple physics proving that so-called drainage materials do the complete opposite of what they’re intended.
Water does not move easily from finer textured material (soil) to coarser textured material (say, stones). As the water trickles through the soil and reaches the stones, it will stop and start to pool in between the layers (in effect, “back filling” the pot) until the soil is fully saturated. Only then will it start to drain — a slow process that keeps the roots sitting in soggy soil far longer than it ordinarily would if the whole pot were filled with soil. Rather than assisting with drainage, the stones restrict it.
The only way to ensure proper drainage is to fill your pot (or in this case, your bathtub) with well draining potting soil (not garden soil, which is much too dense) and make sure the drain hole is unobstructed. When you water, stick your finger in the soil and water only if the first inch or two feels dry. (Moderate watering also encourages the plant roots to reach deep into the soil and grow stronger, rather than staying near the surface where they tend to be weaker.)
With a no-dig garden bed like the one I built for the bathtub, the layers decompose into soft, aerated soil so compaction is not an issue. When I top off the bed for next season, I’ll simply use well rotted compost or amended potting soil.
In the fall, you can also plant fava beans or another cover crop in the clawfoot tub and turn them under the soil at the end of the season, just as you would for a normal garden bed.
One of the things I love about the bathtub planter (besides its quirky aesthetic) is not having to stoop or kneel to harvest. On its perch of stones, the tub comes up just below my hips, putting all the plants at perfect picking height. I can also spray compost tea onto the undersides of the leaves while standing and inspect the plants more easily for pests — small benefits that my back and knees end up thanking me for.
Have any other questions about my clawfoot turned planter? Let me know in the comments!