Greetings, human propagator. I am a cultivated carnation (Dianthus caryophyllus), and I wish to share with you the secrets of my propagation from my own, rooted perspective. To create a new genetic copy of me, you must understand my needs and replicate the conditions that encourage my stem to abandon its leafy duties and become an independent root system.
Your first task is to choose a healthy, non-flowering stem from me, your parent plant. A flowering stem is devoting all its energy to bloom and seed production, not root creation. Seek a stem that is firm, approximately 4 to 6 inches long, and has several sets of leaves. Using a sharp, clean blade, make a diagonal cut just below a leaf node—this is the small bump on my stem from which leaves emerge. This node is a hub of cellular activity and contains meristematic cells, which are undifferentiated and ready to become either root or shoot tissue. The diagonal cut maximizes the surface area from which I can absorb water and, later, form roots. Immediately remove the leaves from the bottom third of the cutting. This is crucial, as any leaves buried in the propagating medium will rot, inviting fungal diseases that will kill me before I can even begin.
I do not require soil at this fragile stage. Instead, place my prepared stem into a container filled with a sterile, low-fertility, and well-draining medium. A mix of half perlite and half peat moss or coconut coir is ideal. This medium provides physical support and retains just enough moisture around my stem without becoming waterlogged, which would suffocate me and cause rot. Before you insert me, moisten the medium thoroughly. Using a pencil or dibber, create a small pilot hole to gently guide me into place. This prevents the delicate cambium layer—the living tissue just under my bark responsible for new growth—from being scraped away as I am inserted.
Once nestled in my moist medium, I require a very specific atmosphere to trigger root formation. You must cover my container with a clear plastic bag or dome to create a miniature greenhouse. This is non-negotiable. It maintains very high humidity around my leaves, drastically reducing transpiration (water loss). Since I have no roots to draw up water, I would quickly wilt and die without this humid enclosure. Place me in a location with bright, indirect light. Direct sunlight will cook me inside my plastic tent. The goal is to provide energy for photosynthesis without excessive heat. In this stable, humid environment, the cells at my wounded node will be triggered to form a callus—a mass of undifferentiated cells. From this callus, adventitious roots will begin to emerge, searching for water and nutrients to sustain my new life.
After two to four weeks, you can test for root development by giving me a very gentle tug. If I resist, it means my new roots are anchoring me. Once rooted, the dangerous part begins: acclimating me to the outside world. You cannot simply remove the plastic dome and leave me exposed. My tissues are incredibly tender and accustomed to 100% humidity. Suddenly exposing me to drier air would be a shock. Instead, open the ventilation gradually over the course of a week—first propping the lid open for an hour a day, then longer, until the humidity inside and outside equalizes. Only when I am fully acclimated should you consider transplanting me into a proper pot with a well-draining potting mix, where I can finally begin my life as a new, independent carnation plant.
