For a school setting, the practical answer is that our planter box factory can build low-profile planters starting at approximately 8 inches (20 cm) in overall height. That very low option works well for shallow-rooted flowers, herbs, sensory plants, and decorative school garden features where easy visual and physical access matters most.

However, lower is not always better for a working school garden. If children will grow vegetables or plants with deeper roots, we usually recommend a finished planter height of 18–24 inches (45–60 cm) for early years and lower primary students. For older children, 24–30 inches (60–75 cm) often gives a comfortable reach while still providing good soil depth, drainage, and root space. The ideal height depends on the children’s age, the plants, and whether the planter will be used while standing or sitting.

As a planter box factory, we can customize school planter boxes to suit your exact reach requirements. We can adjust the height, length, width, soil depth, drainage, and top-edge design. For schools, we recommend rounded or capped edges, non-toxic finishes, stable construction, and clear drainage to support safe, hands-on learning. So yes, we can go as low as 8 inches—but for most school gardens, an 18–24 inch kid-reach height is the sweet spot between accessibility, safety, and healthy plant growth.