|By Carol Yaw
|Propagating plants by cuttings is a highly effective
method of reproducing a plant that is an exact genetic replica. It is an
easy way to multiply your plant collection. It's also an excellent method
to preserve unique and exceptional plants that have different or variable
results when grown from seed.
Generally cuttings are taken from mid-spring through mid-fall. However, with a heat mat or heated propagator they can be rooted earlier. Fall is a good time to take cuttings from annuals and tender perennials like salvia, coleus, fuchsia, geranium and chrysanthemum. Take softwood cuttings from the new growth of plants like forsythia and lavender. Accelerate the root development of semi-hardwood and hardwood cuttings of hydrangea, boxwood, olive, rhododendron, roses and other deciduous plants with a rooting hormone.
Make the cut:
Plant in sterile growing medium:
- Take cuttings early in the morning from young, healthy plants. Use a sterile, sharp knife, pruner or one-sided razor blade to avoid crushing the tissue and prevent the spread of any disease.
- Cut a stem abut 6-10" long below a node (point where the leaf joins the stem.) Strip leaves from the lower 1/3 of the stem. Trim back remaining leaves by about 1/2 their length to reduce transpiration.
- Remove the tip of the cutting to re-direct the plant's energy into its root development.
- Mist cuttings well and put them in a sealed plastic bag until planted in growing medium.
- Use a dibble, pencil or other small, pointed tool to make a hole before inserting cutting.
- Dip the bottom end into a rooting substance to speed up root formation. A rooting hormone increases the number of roots quicker and helps the rooting of more difficult plants.
- Next, insert the cutting into a sterile growing medium.
- Spray with a fine mist.
- Retain humidity. Cuttings have no roots to take up water, but they lose water through their leaves. Cover them with a clear dome, plastic or poly-bag to prevent from drying out.
- A warm, humid environment is the secret to perfect breeding.
- Set in a bright spot out of direct sunlight.
- Keep cuttings moist and ventilate a few minutes daily.
- For faster propagation add a heat mat under your flats or pots. Check for moisture more often if using heat, as they will dry out faster.
- After cuttings have rooted and new growth starts, gradually open the dome daily for about a week to harden them off.
- Water as needed with 1/2 strength fertilizer.
- When root systems are strongly developed, transplant into larger pots. The best soil should hold moisture yet drain freely.
- Keep softwood and tender cuttings in the greenhouse or indoors until spring. In most areas hardwoods can be kept in a cold frame through the winter.
Hard-to-find Propagation Aids