Seeing your once-thriving urban garden struggle? Stunted growth, yellowing leaves, and water that runs right through the soil are classic signs of a root-bound plant. In the confined space of a planter box, roots can circle and choke themselves, but don't worry—it's a fixable problem. Here’s your practical guide to dealing with root-bound plants.
First, confirm the diagnosis. Gently remove the plant from its box. If you see a dense web of roots circling the outer edge and bottom of the root ball, with little soil visible, it's root-bound.
The solution is careful repotting. For a minor case, gently tease apart the outer roots with your fingers to encourage them to grow outward. For a severely bound plant, you may need to make several vertical cuts up the sides of the root ball with a clean knife. This might seem drastic, but it shocks the roots into growing in a new direction.
Choose a new planter box that is only 1-2 inches larger in diameter. Going too big can lead to soil moisture issues. Use fresh, high-quality potting mix. Place the plant at the same depth it was before, fill in with soil, and water thoroughly to help the soil settle.
To prevent recurrence, select plants suitable for your box's size, use high-quality soil that drains well, and consider routine root pruning for perennial plants every few years before they become severely bound. With these steps, your urban oasis will stay healthy and vibrant.