Allen Wilson is a Vancouver gardening specialist. Email Allen Wilson at [email protected]
My friend has given me two indoor plants that she started herself. I would like to start some indoor plants too. Could you share with us some of your knowledge on starting new indoor plants?
Starting new plants is simple for most indoor varieties. Most common indoor plants can be started or propagated by rooting cuttings from branches of existing plants. I recently rooted several cuttings taken from a large coleus plant that has been growing outside. This plant will soon die from the frost. Coleus plants will grow inside. So I decided to start a new plant for inside this winter.
The best cuttings are from the tips of the newest growth. Lower parts of branches can also be used, but they do not root as dependably as the tip cuttings. Cut just above the fifth or sixth leaf. Shorter cuttings will also work. The point where a leaf emerges on the stem is called a node. Trim cuttings just below the bottom leaf node. Then remove one or two of the bottom leaves. At least two leaves should be left attached to the cutting.
Cuttings from most plants will root without rooting hormone, but hormone will speed up the process. Rooting hormone powder can be purchased from many garden stores. It is also available from many sources online. After dipping the end of a cutting in the rooting hormone, place it either in a jar of water or push it into a pot with loose potting soil. Most of the roots will form near the two bottom leaf nodes. Cuttings rooted in water can be planted as soon as they have several roots.
If I am trying to start a 6-inch or larger pot I will place at least three cuttings in the pot. I have placed as many as 10 cuttings to more quickly establish a plant. Water the soil and then cover the cuttings and pot with a clear plastic bag such as used for fruits and vegetables or lining trash cans. The moisture and high humidity inside the bag will keep the cuttings from drying out before they are rooted. Place the cuttings in a warm location out of direct sunlight.
Some plants will form roots in as little as a week. Others may require three weeks or longer. Check to make sure the soil is always moist until rooting takes place. Once the cuttings have several roots, the plastic can be removed and plants can be transferred to stronger light. Direct sunlight should be avoided until plants are well rooted and some growth has taken place.
As soon as plants are rooted I fertilize with liquid house plant fertilizer or Osmocote. After cuttings have made a little growth, I usually pinch (remove) the tips just above the first leaf to encourage branching.
Layering is another propagation technique that sometimes works with plants that do not propagate well with cuttings. Leaves are removed from a piece of stem, which is placed horizontally on the soil while still connected to the plant. Two nodes are covered with soil and roots develop.
After rooting, the stem can be cut from the plant and planted in another pot.