When setting up an urban planter box, a common question arises: does it need a liner? The answer is generally yes, and the right liner is crucial for plant health and the longevity of the box. A liner serves multiple essential purposes. Primarily, it acts as a protective barrier between the moist soil and the planter box material—especially important for wooden boxes to prevent rot and decay. It also helps retain soil, prevents nutrient-rich water from staining surfaces, and aids in managing drainage.
The best liner choice depends on your box material and plants. For most situations, a permeable landscape fabric or a specialized breathable planter box liner is ideal. These materials allow excess water to drain out, preventing waterlogged soil and root rot, while keeping the soil contained. Avoid non-porous materials like solid plastic sheets unless you drill ample drainage holes, as they can trap water. For wooden planters, using a fabric liner over a thin plastic sheet (with holes) can offer a balance of moisture protection and breathability.
Ultimately, a proper liner extends your planter's life, creates a healthier environment for roots, and makes urban gardening more manageable. Always ensure your final setup includes adequate drainage holes at the bottom, regardless of the liner material used.