Absolutely! Adding a trellis to your urban planter boxes is not only possible but highly recommended for climbing plants like peas. It's a fantastic way to maximize your limited growing space vertically. Peas are natural climbers; they use delicate tendrils to grasp onto supports. A trellis provides the perfect structure for them to grow upwards, which improves air circulation, reduces disease risk, makes harvesting easier, and can significantly increase your yield.
You have several easy and stylish options. For a simple DIY solution, insert bamboo stakes or wooden dowels at each end of your planter box and weave garden twine between them in a grid pattern. A classic tomato cage or a piece of sturdy wire fencing (like livestock panel) zip-tied to the box also works perfectly. For a more permanent setup, attach a wooden lattice panel to the back or build a simple A-frame trellis that straddles the box.
When setting up your trellis, ensure it's securely anchored into the soil of the planter to withstand wind and the weight of mature plants. Install it soon after planting your pea seeds or seedlings, so the young plants can begin climbing immediately. With this simple addition, your urban planter will transform into a productive and beautiful vertical green space.