Why Tar Paper Harms Garden Soil (And Better Weed Barriers)

Tar paper leaches petroleum compounds into soil, degrades soil structure, and creates a toxic barrier to beneficial organisms. It's a roofing product, not a garden product.

Safe, Effective Alternatives

Black Plastic (Polyethylene):

• Impermeable—punch holes for planting and drainage.
• Warms soil early; conserves moisture.
• Lasts 1–2 seasons. Remove at season end.

Newspaper/Cardboard (Sheet Mulching):

• 4–6 layers newspaper or single-layer cardboard.
• Wet thoroughly, cover with 2–3 inches straw/compost.
• Decomposes in-place, feeding soil life.
• Replace annually.

Landscape Fabric (Woven Polypropylene):

• Permeable to water/air; blocks light.
• Lasts 5+ years under mulch.
• Cut X-slits for planting.

What NOT to Use

• Tar paper / roofing felt
• Carpet (chemicals, molds)
• Colored plastic (photodegrades into fragments)
• Fresh wood chips directly on soil (nitrogen tie-up)

Best Practice

Newspaper + straw for annual beds. Landscape fabric + wood chips for perennial paths. Black plastic for heat-loving crops (melons, peppers) in cool climates.