Read your weeds to diagnose soil conditions

Observe which weed species dominate your garden area. Dominant populations of specific weeds are indicators of underlying soil conditions: white clover signals low nitrogen, sheep sorrel and moss indicate acidic soil, dandelions and broadleaf plantain point to compaction, lambsquarters and chickweed suggest fertile soil, and sedges or horsetail mean poor drainage.

Why It Works

Weeds thrive where conditions suit them. White clover fixes its own nitrogen and outcompetes other plants where nitrogen is scarce. Dandelion taproots penetrate compacted soil that other species cannot. This principle is documented by Penn State, Michigan State, and LSU extension services. Historically, North American settlers chose farmland based on what vegetation it supported.

Tips

• Look for dominant populations, not single plants — one dandelion does not mean compacted soil
• Acidic soil indicators: sheep sorrel, moss, wild strawberry, hawkweed
• Compaction indicators: dandelion, broadleaf plantain, prostrate knotweed
• Low nitrogen indicators: white clover, black medic, lespedeza
• Wet soil indicators: sedges, rushes, dock, ground ivy
• Use alongside other tests, not as a sole diagnostic tool