Before mulching, the best things to put down are cardboard or newspaper for weed suppression and compost or fertilizer for soil health, after first removing existing weeds and watering the soil well. A weed barrier like cardboard blocks weeds, while compost enriches the soil, and fertilizers provide nutrients for plants, ensuring they're applied before the mulch so they can reach the roots effectively.
The first step for how to lay mulch is to start with a clean surface. Remove dried-up leaves, debris, sticks, weeds, and old mulch from previous years. Also take this time to freshen up the edging along your beds. Use a spade to cut a clean, defined line between your bed and the lawn.
Cardboard is the best thing to use. It decomposes. I only use black landscape fabric if I am using gravel or stone and not planning on planting anything in the area. My trick for cardboard is I load up my cart from warehouse stores. They don't mind and it makes for quick application.
One common type is a nonwoven textile made of plastic fibers, often black, that may be perforated with small holes. The use of landscape fabric is based on the idea that it will either physically intercept weed plants, or that it will keep seeds in the soil from sprouting by blocking sunlight.
Mulching's disadvantages include attracting pests (slugs, rodents, termites), promoting fungal diseases and root rot if applied too thickly or against stems, hindering water/oxygen penetration (leading to suffocation), potentially depleting soil nitrogen (with fresh wood), overheating soil in summer, and increasing initial costs and labor for large areas, with poor quality or fine mulches sometimes repelling water, say Ozbreed Plants and Real Simple.
Mulching's disadvantages include attracting pests (slugs, rodents, termites), promoting fungal diseases and root rot if applied too thickly or against stems, hindering water/oxygen penetration (leading to suffocation), potentially depleting soil nitrogen (with fresh wood), overheating soil in summer, and increasing initial costs and labor for large areas, with poor quality or fine mulches sometimes repelling water, say Ozbreed Plants and Real Simple.
For the best weed suppression in Australia, use thick layers (5-10cm) of chunky woodchips, pine bark, or hardwood chips, as they block sunlight effectively and last well. For veggie patches, straw or lucerne mulch is excellent for nutrients and weed blocking, but needs regular topping up. Inorganic options like landscape fabric or gravel also work but offer no soil improvement.
It dramatically cuts back on time required to remove the weeds that would have sprouted absent their smothering from sheet mulching. Earthworms love to feast on cardboard; as they do, they will both aerate the soil below and add valuable deposits of nutrient rich castings (“worm poop”).
Here are a few strategies for preventing weeds from popping up in your mulch:
Creeping Phlox
This hardy perennial groundcover plant will cover your garden in a pastel-hued carpet of star-shaped flowers in the springtime, and its semi-evergreen foliage will continue to help choke out weeds throughout the remainder of the growing season.
A5: Focus mulch application on healthy garden beds and around plant zones (but not up against trunks). Make sure the beds have good drainage, apply mulch to recommended depths (typically 2–3 inches), and avoid piling it too deep or too close to structures or stems.
The best ways to kill weeds permanently include:
Ideally, you would apply mulch in the spring after the soil has warmed and before weeds have emerged, but you can apply mulch anytime of the year. If you apply before the ground has thawed, it might delay your soil warming in the spring—but if winter is when you have time to apply mulch, then do it in winter.
Removing mulch before putting down new mulch is typically not necessary. Good mulch breaks down over time and adds nutrients to the soil. The best way to lay over old mulch is to rake the area flat before you start.
October isn't too late to spray for many weeds, especially perennial and winter annuals like clover and dandelion, as they actively store energy for winter, making fall applications highly effective for root control; however, effectiveness decreases with colder soil and frost, so aim for mild, dry days when weeds are still green and growing, but stop before deep freezes.
How do I prevent weeds when creating a new mulch bed? One way to prevent weeds when creating a new bed is to use landscape fabric. Once trees, plants, and/or flowers are planted and bed edges are cut, laying down landscape fabric prior to mulching will prevent the germination of weeds.
To prepare the soil of your mulch bed, use a rake to remove any organic material like leaves, seeds or sticks. This will also help get rid of any debris that was created when you trimmed your trees and bushes.
Get Rid of Weeds Before Mulching
It's much more effective to remove large and numerous weeds before adding mulch to your garden, as they can otherwise reemerge or continue spreading beneath it.
Priming Cardboard For Sheet Mulching
One reason is that cardboard can be very slow to fully decompose in drier climates. If cardboard is able to dry out, it's going to take a lot longer to disappear into the soil. However, in a wetter climate like mine, cardboard can rot down under mulch within just six months or so.
Pine needles, grass clippings, and shredded leaves are free alternatives to landscape fabric. They're also environmentally friendly and easy to spread in your garden and flower beds. Pine needles, mulched leaves, and recycled grass clippings prevent soil erosion, hold onto moisture, and enrich the soil with nitrogen.
Cardboard boxes are hydrophobic to a certain degree, and if allowed to dry out, they can prohibit water from reaching plant roots. In established landscape beds, it is best to stick to just a three-inch layer of mulch. More options for mulch can be found in HGIC Factsheet 1604 Mulch.
Finally, avoid large, bark type mulch or big wood chips. Since these big pieces take a long time to decompose, and they end up depriving the soil and plants of nutrients.
Fill a spray bottle with white vinegar and spritz them fully, trying to get as close to the roots as possible. Normal vinegar will also do the job, helping you to get rid of weeds permanently.
Walkable Ground Covers That Are Easy to Control: