Yes—when you order from a planter box factory, pre-drilling holes for trellis attachments is usually possible as a custom option. The key is to confirm the details before production. Factories can pre-drill pilot holes, through-holes, or countersunk holes depending on your trellis brackets and the planter material. For wood and composite planters, pre-drilling helps prevent splitting and makes installation easier. For metal planters, holes may be punched or drilled during fabrication; for HDPE or plastic planters, the factory can drill clean holes that match your bracket hardware. To get an accurate result, provide the trellis attachment model, a drawing or template, the screw or bolt size, hole diameter, thread type, hole spacing, and the height where the trellis should sit. If you do not have a template, many factories can use standard spacing or create a simple jig for repeatable placement. You should also decide whether you need pilot holes only, through-holes for bolts, or countersunk holes for flush screws. Stainless steel or rust-resistant hardware is recommended for outdoor use. The factory should avoid placing holes too close to the rim, joints, or edges, because that can weaken the planter or cause cracking. A quick sample or 3D drawing approval is the best way to prevent mismatches. MOQ, tooling, and lead time may affect whether pre-drilling is free or added as a small custom charge; simple drilling is often easy to include, while complex templates or reinforcement may cost more. Before shipping, the factory should check hole positions, clean debris, and pack the planters so the drilled areas are protected. In short, yes, a planter box factory can pre-drill holes for trellis attachments, but the best results come from clear specifications, material compatibility, and written approval before mass production.