Should You Use Landscape Fabric Under Mulch? (Probably Not)

Landscape fabric is one of the most-sold landscaping products and one of the most regrettable. It promises weed-free beds forever. It delivers a tangled mess by year three. Here's the honest take.

How it's supposed to work

A woven or non-woven fabric laid over soil and covered with mulch. Blocks weeds from below. Lets water and air through (theoretically). Lasts for years (theoretically).

What actually happens

1. Year 1: works beautifully, no weeds.
2. Year 2: organic debris (leaves, mulch breakdown, dust) builds up on top of the fabric. Weed seeds blow in and germinate in this layer.
3. Year 3: weed roots grow down through the fabric and anchor in the soil below. Pulling them now means pulling the fabric.
4. Year 5: fabric is full of holes, surrounded by weeds with roots through it, and impossible to remove without destroying the bed.

When fabric does work

• Under pathways covered with rock or gravel (no organic top layer)
• Under hardscaping (patios, decks)
• As a short-term solution before establishing ground cover (then plan to remove)

What to use instead

Cardboard. Flatten cardboard boxes, lay them on the soil, wet them down, cover with 3–4 inches of mulch. Cardboard kills existing weeds, blocks new ones, and decomposes into soil in 6–12 months — leaving you with great soil and a clean bed.

Or just thick mulch

3 inches of mulch alone stops 80–90% of weed germination. Refresh annually with 1" and you'll never need fabric.

Other problems with fabric

• Blocks earthworms and soil organisms from doing their work
• Heats soil more than bare ground
• Plastic fabric (cheap kind) sheds microplastics over time
• Restricts root growth for trees and shrubs planted through it
• Looks terrible when exposed

If you already have fabric

If it's been in place over 3 years and weeds are establishing, remove it now. Yes, it's miserable work. Yes, it's worth it. The bed will be healthier without it within one season.

The professional consensus

Most experienced landscapers stopped recommending fabric a decade ago. The exception is the cheapest installers who use it to claim 'weed-free' to clients who'll be someone else's problem in five years. Don't be that future homeowner.