Removing Algae and Lichen from Patios and Driveways

Removing Algae and Lichen from Patios and Driveways

Safety First

Both Sodium Hypochlorite and Azpects Black Spot Remover are powerful chemicals. Use them responsibly:

  • Wear protective gloves, goggles, and old clothes — try our PPE Safety Pack.
  • Ensure good ventilation if using in enclosed or walled areas.
  • Keep pets and children away from treated zones.
  • Test on a small inconspicuous area before full application.

Option 1: Using Sodium Hypochlorite (Bleach-Based Solution)

Best for: Quick removal of green algae, moss, and surface-level organic staining. Ideal for large concrete areas, block paving, and stone patios.

What You Need:

  • Industrial Sodium Hypochlorite (10–15% concentration)
  • Pump sprayer or watering can
  • Pressure washer (optional but ideal)
  • Stiff brush
  • Water source

Step-by-Step Instructions:

  1. Clear the Area: Remove furniture, planters, and sweep away debris. Dry conditions are ideal. Avoid rainy days.
  2. Dilute the Sodium Hypochlorite: Mix 1 part Sodium Hypochlorite with 4–5 parts water.
  3. Apply Generously: Soak the affected area thoroughly, including cracks and joints.
  4. Dwell Time: Leave for 15–30 minutes, keeping the surface damp.
  5. Agitate if Needed: Scrub stubborn patches.
  6. Rinse Well: Use a hose or pressure washer. Avoid run-off into plant beds.
  7. Repeat if Necessary: Very old or thick growth may need a second round.

Option 2: Using Azpects Black Spot Remover

Best for: Removing stubborn black lichen spots and deep-rooted organic stains. Especially effective on natural stone, block paving, and decorative surfaces.

What You Need:

Step-by-Step Instructions:

  1. Surface Preparation: Sweep the area clean. Apply in dry, warm weather — avoid rain for at least 4–6 hours after application.
  2. Apply Neat: Do not dilute. Apply directly onto black spots until soaked.
  3. Let It Work: Leave for 2–4 hours or until spots fade. Bubbling or fizzing is normal.
  4. Agitate: Use a stiff brush on thick lichen patches.
  5. Rinse Thoroughly: Use a hose or pressure washer, avoiding flower beds and ponds.
  6. Repeat for Severe Infections: Apply again a few days later if needed.

Maintenance Tips to Prevent Regrowth

  • Apply a biocide or patio sealer every 6 to 12 months.
  • Keep surfaces clean and dry — sweep regularly.
  • Trim plants or trees that block sunlight.
  • Spot-treat with diluted Sodium Hypochlorite every few months.

What to Avoid

  • Never mix bleach with acidic or ammonia-based products — it’s dangerous.
  • Don’t allow cleaners to dry on the surface — this can cause staining.
  • Avoid overuse on delicate stones without prior testing.
  • If unsure, hire a professional.

Comparison Summary

Sodium Hypochlorite

  • Excellent at removing green algae and moss
  • Moderately effective on black lichen
  • Use with care on natural stone
  • Works quickly (15–30 minutes)
  • Requires dilution
  • Very cost-effective

Azpects Black Spot Remover

  • Best for black lichen spots
  • Safe for natural stone
  • Works slowly (2–4 hours+)
  • Ready to use
  • Higher cost, but excellent performance

Final Thoughts

For general cleaning, ProClean Moss and Algae or Sodium Hypochlorite is fast and economical. To tackle tough black spots, especially on stone, EASYCare Black Spot Remover is your go-to.

Using them in sequence — bleach first, then black spot remover — gives a professional-grade clean that transforms outdoor spaces.

Still not sure what’s best? Contact us for expert advice.

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