White stains on plants & walls

1. High Calcium or Magnesium (Hard Water)

• Appearance: Fine, chalky white film on leaves or soil surface after watering.

• Cause: When bore water evaporates, calcium carbonate or magnesium salts precipitate out and deposit on leaves.

• Test: Do a simple hardness or TDS (Total Dissolved Solids) test on the bore water.

• Fix:

  • Use drip or sub-surface irrigation to keep water off foliage.

  • Install a softening or acid-dosing system (e.g., dilute citric acid or CO₂ dosing to lower pH).

  • Periodic leaf washing with rainwater can help remove residue.

2. High Sodium or Chloride Content (Saline Water)

• Appearance: White crusts on leaf tips and soil; plants may show leaf burn or stunted growth over time.

• Cause: Evaporation leaves behind sodium chloride or similar salts.

• Test: Conduct an EC (electrical conductivity) test or full lab analysis for salinity (mg/L or µS/cm).

• Fix:

  • Leach salts from the soil by flushing with good-quality water.

  • Consider blending bore water with rain or scheme water if feasible.

  • Choose salt-tolerant species if salinity remains high.

3. Iron or Manganese Oxidation

• Appearance: White film that may later turn rusty or grey; often around sprinkler heads or leaf veins.

• Cause: Dissolved iron or manganese oxidises on exposure to air, leaving mineral residues.

• Test: Iron/manganese field kits or laboratory water analysis.

• Fix:

  • Aeration followed by filtration or treatment with sequestrants like BoreSaver Ultra C (biodegradable and NSF-certified).

  • Keep irrigation systems clean to prevent clogging.

4. Chemical Precipitation (High pH Water)

• Appearance: Milky or chalky spots when water dries.

• Cause: High-pH bore water (>8) causes calcium carbonate to precipitate.

• Fix:

  • Test water pH.

  • If high, dose with a mild acid (citric or phosphoric) to bring it down near 6.5–7.0.

5. Low Plant Uptake or Residue Build-up

• If the white film doesn’t harm plants, it might just be superficial mineral residue.

  
  

  Continue monitoring — if growth or leaf colour declines, arrange a water chemistry and soil EC test.