Mulching against weeds
Mulching is a lever against weeds because it blocks light. It is generally applied after weeding the plot.
This method also has the advantages of retaining soil moisture, maintaining its temperature, and protecting against erosion.
Organic mulching
It is important to choose a mulch adapted to the crop and soil, so you must consider:
- the pH of the mulch and that required by the crop
- the nutrient needs of the soil
- the absence of seeds.
Diversification of mulches is important because it prevents soil depletion, meets its needs, and also promotes fauna diversity.
| Ramial Chipped Wood (RCW) | Straw and hay | Hemp straw | Flax straw | Compost | Grass clippings | Miscanthus | |
|---|---|---|---|---|---|---|---|
| Thickness | 15 cm | 10 - 20 cm | 10 cm | 10 cm | 6 - 7 cm | 5 - 20 cm. Thickness is less if the grass is fresh than if it has been dried | 10 cm |
| Cost | 0 - 4.5 €/m2 | 0.5 - 2 €/m2 | 5 - 10 €/m2 | 2 - 10 €/m2 | 1.5 - 10 €/m2 | ||
| Duration | 2 years | A few months | 2 - 3 years | 1 - 2 years | A few months | 2 years | |
| Advantages | Retains soil moisture well
Slow degradation because composed of lignified material Local |
Locally available
Low cost Allows soil to breathe |
Promotes soil life | Enriches soil with humus thanks to rapid decomposition | C/N around 10 so nutrients are quickly available | May be locally available
Neutral pH | |
| Disadvantages | Rapid degradation | High cost | Rapid degradation | May ferment and thus raise temperature | High cost
Strong wind uptake if site is exposed. |
Advantages
- Adds organic matter.
- Improves soil structure.
- Promotes biodiversity.
Tarp
The tarp is an easy-to-install alternative that offers interesting opacity to fight weeds. The drawback is that the tarp is not always biodegradable, which can pollute soils.
Biodegradable fabric
These fabrics are biodegradable alternatives to tarps; just be careful that they do not serve as a planting support for weed seeds that might stick to them.
They are made of jute fibers, hemp, cotton, flax, or coconut.
Living mulch
Living mulch corresponds to cover crops; it can be advantageous for weed control but also for fixing nitrogen if it includes legumes. However, it requires closer management and thoughtful composition.
Feedback
Experience of the Interprofessional Technical Center for Fruits and Vegetables (CITFL)
A study conducted by CITFL[1] established the impact of different mulches on weed cover in market gardening.
| Type of mulch | Quantity or thickness | Weed cover level |
|---|---|---|
| RCW | 6.8 kg/m2 | 15% |
| Forest mulch | 9 kg/m2 | 7% |
| Grass clippings | 8.6 kg/m2 | 2% |
| Wheat straw | 10 kg/m2 | 10% |
| Paper mulch | 112 g/m2 | 0% |
| Polyethylene mulch | 20 µm | 0% |
Farmers' experiences
Sources
- Pascal Balleux, Damien Gillain. 2021. Good agroforestry practices. Dossier - Mulching against weeds. [12/02/2026]. https://reseauwallonpac.be/sites/default/files/dossier_-_paillages_contre_les_adventices.pdf
- Charlotte Berthelot, Vanessa Demoisson, Loïc Fouyer, Romane Jean, Mélanie Riou. Tenace, a project to eradicate weeds. [12/02/2026]. https://www.ctifl.fr/tenace-un-projet-pour-venir-a-bout-des-adventices-infos-ctifl-378
- F. Berger, Ph. Delval, M. Gayrard. 2018. Covering the base of plantations to fight weeds. [12/02/2026]. https://ecophytopic.fr/leviers/proteger/recouvrir-le-pied-des-plantations-pour-lutter-contre-les-adventices
- Shahid Farooq, Mubshar Hussain, Noman Mehboob, Wagas Ahmed Minhas, Hafeez Ur Rehman, Muhammad Yahya. 2022. The Influence of Different Crop Mulches on Weed Infestation, Soil Properties and Productivity of Wheat under Conventional and Conservation Production Systems. [12/02/2026]. https://www.mdpi.com/2223-7747/12/1/9
- Serres Val-de-Loire. 2025. Different types of mulching and their uses. [12/02/2026]. https://www.serresvaldeloire.com/actus-conseils/paillage-sol/les-differents-types-de-paillage-et-leurs-usages/
