How heavy are large concrete-look planters once filled?

Very. Specialist community threads we read repeatedly warn that once you fill a 15-inch+ planter with damp soil, it becomes effectively immovable — a plant caddy with casters is a common recommendation before planting. Plastic-stone composites like Veradek's Demi line are noticeably lighter than true concrete like Kante, which matters on balconies and decks.