Plant propagation is the straightforward process of creating new, genetically identical plants from a parent specimen. Many houseplant enthusiasts choose this method to expand their indoor collection without the expense of purchasing new pots. Propagating also provides a way to share favorite varieties with friends or to revive an aging plant that may be becoming leggy or sparse. By understanding the different techniques, you can successfully multiply most popular houseplants using just a few simple tools and a little patience.
Essential Preparation and Supplies
Before making any cuts, preparing your tools and selecting the right time for propagation significantly increases the chance of success. Sterilize your cutting instruments, such as pruners or a sharp knife, with rubbing alcohol to prevent the transfer of pathogens. Taking cuttings during the plant’s active growing season, generally spring and summer, allows them to establish roots more quickly.
The choice of rooting medium depends on the method, but common options include fresh water, perlite, or a well-draining potting mix. Some growers opt to use rooting hormone, a product containing synthetic compounds that mimic the natural plant growth hormone auxin. Applying a light dusting of powder or gel hormone to the cut end of a stem or leaf can encourage faster root development, although it is not necessary for all plant types. This product should never be used in water propagation, as the substance will simply wash away and become ineffective.
Propagating Using Stem and Leaf Cuttings
Stem Cuttings
Stem cuttings are the most common propagation method for vining plants like Pothos and Philodendron. To take a cutting, locate a node, which is the small bump on the stem where a leaf or aerial root emerges, and cut the stem about half an inch below it. The node contains the undifferentiated cells required to produce new roots. You should remove any leaves that would be submerged below the water or soil line to prevent rotting of the organic material.
The cutting can be placed in a glass of water, which allows you to monitor root growth easily, or directly into a moist, well-aerated soil mix. Cuttings rooted in water often develop specialized, thin water roots that are distinct from those grown in soil. When planting directly into soil, dipping the node in rooting hormone can be beneficial, as the hormone remains in contact with the tissue.
Leaf Cuttings
Leaf cuttings are employed for plants that lack easily accessible nodes, such as African Violets and Snake Plants. For African Violets, the entire leaf and its petiole, or stem, are planted into a moist medium. Snake Plants (Sansevieria) are propagated by cutting a healthy leaf into multiple segments, typically two to four inches long.
It is necessary to keep track of which end of the Snake Plant segment was facing down, as roots will only form from the basal end. Allowing the segments to sit out for a few days before planting lets the cut ends develop a protective callus, which helps prevent rot in the soil. Propagating a variegated Snake Plant using leaf segments will often cause the new plant, or pup, to lose the white or yellow markings and revert to a solid green color.
Propagating Through Division and Separation
Division
Division is a propagation method that involves physically separating a mature plant’s root ball into smaller, complete plants. This technique is appropriate for plants that grow in clumps or have multiple crowns, such as Peace Lilies, Ferns, and some clumping succulents. The process is best performed during repotting when the plant is already out of its container.
Gently remove the plant from its pot, and brush away excess soil to expose the root structure. Identify natural divisions within the root ball, ensuring each section has its own set of healthy roots and foliage attached. For densely matted or root-bound specimens, a clean, sharp knife may be necessary to separate the sections.
Separation
Separation is used for plants that produce offsets or “pups,” which are small, complete plantlets that grow on runners or directly from the base of the parent. Spider Plants frequently produce small plantlets on long, arching stems, while succulents like Aloe often produce pups at the soil line. These offsets usually have small, pre-formed root systems and can be gently twisted or cut away from the mother plant. Each separated piece is then potted individually into fresh soil.
Acclimating New Plants and Post-Propagation Care
After a cutting has successfully rooted in water, the transition to soil must be handled carefully to prevent transplant shock. The cutting is ready to be potted when its roots are at least one to two inches long. Since the delicate water roots are not adapted to extracting moisture and nutrients from soil, a gradual process known as hardening off is beneficial.
One effective method involves replacing a small amount of the water with moist soil each day until the container is mostly filled with potting mix. This slow introduction allows the fragile water roots to begin developing sturdier soil roots. Once fully transitioned, the new plant should be potted in a small container with fresh, well-draining soil and watered thoroughly.
New plants and divisions should be placed in an area that receives bright, indirect light, as intense direct sun can scorch the still-developing root system. Maintaining high humidity around the new growth also helps the leaves absorb some moisture while the roots establish themselves. You can achieve this using a humidity dome or by placing the pot on a tray of pebbles filled with water. Avoid fertilizing the newly potted plant for several weeks to allow the roots to recover from the stress of propagation.