Slabs are the final step in a slab production system, most commonly used for greenhouse tomatoes, cucumbers, peppers and cut flowers. Start with A-OK cubes, then set rooted cubes into Delta blocks. When plants are fully rooted in the Deltas, simply set on top of the slabs for the remainder of production. Utilize drip irrigation (placed in the Delta block). Use slabs with the UV resistant poly sleeve in place - cut the sleeve to reveal the slab when placing the Delta block.