Glossary, Water
Leaching
Short definition
Leaching is water carrying excess salts or nutrients down through soil and out of the root zone.
It is the idea behind a salt flush: water the pot or bed thoroughly so that dissolved salts move out through the drainage holes or deeper into the ground.
Why it matters
Leaching also washes useful nutrients away, which is why plants in free-draining sandy soil often need more regular feeding.