How does tillage affect water retention?
Written by
Nguyen Minh
Reviewed by
Prof. Martin Thorne, Ph.D.Tillage methods greatly affect the soil's ability to retain water by breaking down even essential soil structure. I have seen tillage completely dismantle the natural aggregates that provide moisture retention in soil in my community garden in Utah. The aggregates created small pores that act as sponges filled with water for plant roots. Tillage destroys the fragile systems, forming compaction and decreased infiltration capacity.
Structural Damage
- Destroys soil aggregates creating moisture-holding pores
- Breaks fungal networks that bind soil particles
- Reduces pore space available for water storage
- Creates compaction layers below tillage depth
Water Retention Consequences
- Decreases infiltration rates by 30-60%
- Increases surface runoff during rainfall
- Accelerates evaporation from exposed soil
- Promotes crust formation that blocks water entry
No-Till Alternatives
- Preserve natural soil structure and pore networks
- Use cover crops to maintain soil integrity
- Apply mulch instead of turning soil
- Employ broadfork for minimal soil disturbance
Use no-till systems to conserve moisture. I use cover crops like winter rye in my garden, which naturally aerate the soil. Then, in the spring, I cut them off at ground level and let the roots decompose. This preserves the pore structures and keeps the soil undisturbed. The moisture retention factor improves significantly over time.
If tillage is needed, time it well. Work the soil when moderately dry, not wet. Test by picking up a handful and squeezing it; the soil should crumble, not form a solid ball. I only till my vegetable beds in the fall, after harvest. Tillage in the spring harms the soil life that is beginning to emerge. Proper timing will enable your soil to recover more quickly.
Transition slowly from conventional tillage. Start with one garden bed per year initially. Begin to broadfork beds for deeper aeration, rather than soil inversion. Use compost, where the surface layer keeps it locked in place while earthworms incorporate it into the soil. You will notice the first improvements in water retention and healthier plants within three years.
Read the full article: 7 Proven Water Retention Soil Methods
