What Is the Best Rooting Compost for Cuttings?

The rooting medium you choose has a direct impact on whether cuttings succeed or fail. A newly inserted cutting has no roots to absorb water or nutrients — its only lifeline is direct absorption through the cut base. The rooting medium must be moist enough to prevent desiccation, open enough to allow the oxygen that root initials need, and low enough in nutrients to avoid scorching the tender new roots as they emerge. Standard multipurpose compost fails on multiple counts, which is why many gardeners who switch to a proper rooting mix see immediate improvements.

Why Multipurpose Compost Is Not the Answer

Multipurpose compost is designed to support growing plants that already have root systems. It is relatively nutrient-rich (damaging to emerging root tips), often too fine-textured (reducing oxygen levels), and tends to retain too much water (creating anaerobic conditions at the cutting base). It may also contain large peat or coir chunks that create large air pockets rather than consistent contact with the stem. Using it for cuttings often works for the most vigorous species — willows, currants, mint — but fails for anything requiring a longer rooting period.

The Standard DIY Rooting Mix

The most reliable general-purpose rooting medium is a 50:50 mix of perlite and coir (coco coir). Perlite is inert, extremely well-draining, and ensures excellent aeration around the cutting base. Coir holds moisture evenly, has near-neutral pH, and is sterile from the block. Together they create a medium that stays consistently moist without becoming waterlogged, and provides excellent oxygen availability. This mix suits most softwood and semi-ripe cuttings. It contains no nutrients — correct for rooting purposes — so pot on into proper compost promptly once roots have formed.

Alternatives and Adjustments for Specific Cutting Types

Hardwood cuttings in open ground do not need a specially prepared medium — gritty garden soil is adequate. For semi-ripe cuttings of difficult evergreens, adding a small amount of fine bark to the perlite-coir mix can improve results. For leaf cuttings of succulents, replace coir with coarse sand for even better drainage. Commercial cutting compost sold in bags is usually a fine blend of peat or coir with perlite, and works well as a ready-made option. Avoid anything described as ericaceous for general use — the low pH suits some species but is incorrect for the majority.

Preparing and Wetting the Medium Before Use

Mix your rooting medium in a bucket and wet it thoroughly before filling trays or pots. Coir especially can be stubborn to wet from dry — it tends to repel water initially. Pour warm water onto dry coir and mix repeatedly, adding more water until the medium is evenly damp throughout. Squeeze a handful: it should feel moist and just hold together but release no more than a drop of water when squeezed hard. Pre-moistening before inserting cuttings ensures consistent moisture contact at the cutting base from the moment you pot up.