Propagation Guide

Air Layering

Rooting on the parent plant before separation

Air layering is the safest propagation method for rare or expensive aroids — roots are developed while the cutting is still attached to and being fed by the parent plant. Only after a healthy root system has formed is the cutting removed. The result is a much higher success rate than standard stem cuttings, at the cost of a little more preparation. It's particularly recommended for Philodendron spiritus-sancti and other plants where losing a cutting would be a significant financial loss.

Best For

  • Rare or expensive climbing aroids where cutting failure would be costly
  • Philodendron spiritus-sancti, patriciae, and other slow-growing species
  • Plants with thick stems that root more reluctantly than typical aroids
  • Any climbing aroid where you want near-guaranteed success

What You Need

  • Sharp, sterilised blade
  • Moist sphagnum moss (thoroughly wetted then squeezed to remove excess water)
  • Clear plastic film or cling wrap
  • Zip ties, twist ties, or grafting tape to seal the sphagnum
  • Rooting hormone (optional but beneficial)

Step by Step

  1. 1

    Select a section of stem

    Choose a healthy section of stem with at least one node, ideally with an aerial root already present. The section should be below a healthy leaf so the plant can continue photosynthesising above the wound.

  2. 2

    Create a wound

    Using a sterilised blade, make a shallow upward cut or a ring of removed bark around the stem at the node. The goal is to interrupt the flow of nutrients downward — this triggers root production at the wound site. Do not cut more than halfway through the stem.

  3. 3

    Apply rooting hormone

    Dust the wound surface with rooting hormone powder or apply gel directly to the cut. This accelerates root initiation.

  4. 4

    Pack with moist sphagnum

    Take a generous handful of moist sphagnum and pack it firmly around the wound site, forming a ball 6–10 cm in diameter. The entire node and wound must be covered and in contact with the sphagnum.

  5. 5

    Wrap in plastic

    Wrap the sphagnum ball tightly with clear plastic film, sealing both top and bottom with zip ties or tape. The package must be airtight to maintain moisture. Clear plastic lets you monitor root development without disturbing the setup.

  6. 6

    Wait for roots

    Leave undisturbed for 4–12 weeks. You will see roots growing through the sphagnum — wait until roots are 3–5 cm long and clearly visible through the plastic before proceeding.

  7. 7

    Cut and pot

    Once roots are established, cut the stem just below the sphagnum ball. Remove the plastic but leave the sphagnum intact around the roots — it will integrate naturally into the potting medium. Pot into a well-draining substrate and maintain high humidity for 2–4 weeks.

Tips for Success

  • Placing the plant in higher light during air layering speeds up root production by increasing the plant's metabolic activity
  • If the sphagnum appears to be drying out through the plastic wrap, inject a small amount of water with a syringe through the wrap rather than unwrapping
  • For the highest-value plants, air layer multiple nodes simultaneously as insurance
  • The parent plant suffers minimal stress and will often push new growth from below the wound

Common Mistakes

  • Not wounding deeply enough — a superficial cut may not trigger root initiation
  • Using sphagnum that is too wet — waterlogged sphagnum encourages rot rather than rooting
  • Cutting the stem before roots are fully established — wait until you can see a good root mass, not just the first hairlike roots
  • Not sealing the plastic completely — moisture loss dramatically slows root production