Yes. A planter box factory can create self-watering inserts for large concrete planters, but the work should be treated as a custom fabrication project rather than a standard product purchase. Large concrete planters vary widely in interior dimensions, wall thickness, drainage, weight, and exposure conditions, so the insert must be designed to fit the specific planter and planting plan.

A capable factory can produce a separate liner-style insert with a lower water reservoir, a wicking layer or wick columns, a growing-media support platform, an overflow outlet, and ventilation points. It can also build the system as a modular unit so that large planters can be assembled on site, which is often easier than moving a single oversized insert. Suitable materials include durable, UV-stable plastics and fabricated composite panels, depending on the required strength, root space, and lifespan.

The main technical considerations are reservoir capacity, overflow safety, weight distribution, root aeration, and access for inspection or cleaning. Because concrete planters can be heavy and may already have drainage holes, the insert design must prevent waterlogging while allowing excess water to escape predictably. The factory should confirm interior measurements, assess drainage paths, and recommend whether the concrete shell needs sealing, a raised base, or additional ventilation. Prototyping is strongly advised for very large or irregular planters.

In practice, a planter box factory with experience in custom liners, rotational molding, thermoforming, or fabricated plastic assemblies can absolutely create effective self-watering inserts for large concrete planters. The best results come from a factory that offers design review, material selection, sample fitting, and clear installation guidance. With the right engineering, a concrete planter can gain the convenience of self-watering while preserving its architectural appearance and long-term durability.