Philodendron bipinnatifidum, now often classified as Thaumatophyllum bipinnatifidum, is a popular tropical plant known for its large, deeply lobed leaves and trunk-forming growth habit. Propagating this aroid allows growers to create new plants from existing mature specimens. Successfully initiating new growth requires careful handling and specific environmental conditions for the cutting to establish itself. This guide provides the step-by-step instructions necessary for successful home propagation.
Essential Supplies and Preparation
To begin the propagation process, clean and sharp cutting instruments are needed, such as bypass pruners or a sterile horticulture knife. The use of sterilized tools is important for preventing the introduction of pathogens, which can cause rot or disease in the parent plant and the new cutting. Wiping the blade with isopropyl alcohol before and between cuts ensures a clean procedure.
Selecting appropriate plant material is the preliminary step to propagation success. Look for a section of the stem that includes a prominent node, which is the slightly swollen area where a leaf or aerial root emerges. These nodes contain the meristematic cells necessary to initiate new root growth.
Several mediums support successful root initiation for this type of aroid. Sphagnum moss, which retains moisture while allowing air circulation, is a highly favored choice for rooting because its slightly acidic pH can deter some pathogens. Alternatively, a coarse mixture of perlite and vermiculite or simply placing the cutting directly into water can also be effective, though water rooting may result in roots that are initially fragile.
The application of a rooting hormone, available in powder or liquid form, can enhance the speed and reliability of root development. These products stimulate rapid cell elongation and division at the wound site. When using the powder, the cut end should be lightly dusted just before insertion into the rooting medium, ensuring full coverage.
Step-by-Step Propagation Methods
The stem cutting method involves isolating a section of the stem containing at least one node, though two or three nodes are preferable for better success. Make a clean, angled cut about one to two inches below the chosen node using the sterilized tool. An angled cut increases the surface area for hormone application and water absorption.
After the cut is made, allow the wound surface to dry out for a few hours or overnight. This callousing process seals the cut, reducing the chance of infection once the material is placed in a moist medium. Apply the rooting hormone lightly to the calloused area before planting, focusing the application where new roots will emerge.
Carefully insert the treated end of the cutting into the prepared rooting medium, ensuring the node is fully submerged or in direct contact with the moss or mixture. If using sphagnum moss, ensure it is thoroughly moistened but not saturated to prevent the developing roots from suffocating. Place the container in a location ready for the rooting phase.
Air layering is often the preferred method for propagating large, mature specimens of T. bipinnatifidum as it allows roots to form while the section remains attached to the parent plant. This technique minimizes the shock the cutting experiences and generally provides a higher establishment rate for larger plant pieces. The process involves inducing root growth directly on the stem.
Identify a suitable area on the stem, typically just below a node, and carefully score or remove a small, one-inch-wide ring of outer bark entirely around the circumference. This injury encourages rooting above the cut site. Apply rooting hormone to the exposed area to stimulate root initiation.
Wrap a generous amount of damp sphagnum moss completely around the treated section of the stem. Secure the moss in place using clear plastic wrap, tying it tightly above and below the moss to create a sealed, high-humidity pocket. Once a dense root network is visibly growing throughout the moss, make a clean cut directly below the root ball for separation and immediate potting.
Establishing the New Plant
The newly placed cutting requires bright, indirect light to encourage healthy root development without causing leaf scorch. An ideal temperature range for rooting is between 70 and 85 degrees Fahrenheit. Maintaining high relative humidity is beneficial, often achieved using a humidity dome or a clear plastic bag to reduce transpiration stress.
Root growth should be monitored regularly, which is easiest when using clear containers or transparent moss bags. Signs of success include new leaf emergence or resistance when the cutting is very gently tugged. Avoid disturbing the cutting too frequently, as this can damage tender new root tips and set back the establishment process.
The waiting period for root development generally takes several weeks to a few months, depending on environmental conditions. Roots are considered ready for potting when they are visibly robust and measure approximately two to three inches in length. Roots that are too short may struggle to establish themselves in a new, less humid potting medium.
When the roots are adequately developed, transition the cutting from the rooting medium to a permanent potting mix. Use a well-draining aroid mixture, often containing chunky components like orchid bark, charcoal, and perlite, to ensure proper aeration. The new pot should only be slightly larger than the root ball to prevent the soil from remaining too wet.
After transplanting, the new plant may experience temporary transplant shock, manifesting as slight wilting. Place the pot in a slightly shadier area for the first week, then gradually return it to bright, indirect light. Resume a regular watering schedule only once the plant shows signs of settling into its new container.