The Role of Earthworm Tunnels in Improving Sub-Surface Drainage

Earthworm tunnels improve sub-surface drainage by creating continuous, stable vertical macropores that bypass compacted soil layers. When heavy rain or irrigation saturates a raised…

How to Use a Soil Auger to Create “Drainage Chimneys”

A drainage chimney is a vertical, aggregate-filled column drilled straight down through the bottom of a waterlogged raised bed to breach an impermeable subsoil…

Identifying “Iron Ochre” Slime That Clogs Raised Bed Drainage

If your raised bed drainage outlets or weep holes are clogged with a thick, rust-colored, jelly-like goo, you are dealing with iron ochre slime.…

Does Adding Perlite Actually Improve Drainage in the Long Term?

Perlite improves raised bed drainage immediately, but it is an ineffective long-term solution for permanent outdoor beds. While it creates instant pore space in…

The “Drainage Hole” Math: How Many Does a Containerized Bed Need?

A containerized raised bed (one with a solid manufactured bottom) requires a minimum drainage outlet area of 1 to 2 square inches of total…

Why Over-Saturated Soil Kills Beneficial Aerobic Microbes

Over-saturated soil kills beneficial aerobic microbes by physically displacing oxygen from the soil’s pore spaces with water. When gas exchange ceases, the diffusion of…

How to Slope the Ground Under Your Bed to Prevent Water Pooling

When water pools beneath an open-bottom raised bed, the native subsoil cannot evacuate drainage water as fast as the bed sheds it. This traps…