TAKING CUTTINGS

Photo: Softwood hydrangea cutting.

Propagation by stem cuttings is the most common way to increase your woody ornamental plants and herbs. Most common shrub cuttings root easily.

A greenhouse isn’t necessary to propagate stem cuttings but keeping the humidity high is important. If only a few cuttings are required then a plant pot covered with polythene (figure1) or an old plastic bottle with the base cut off would do the trick. For more cuttings, seed trays with a plastic lid would be ideal.


TYPES OF STEM CUTTINGS
The four main types of stem cuttings are herbaceous, softwood, semi-hardwood and hardwood.

Herbaceous cuttings
These are made from non-woody, herbaceous plants such as chrysanthemums and dahlia. A 3-5 inch (7-10cm) piece of stem is cut from the parent plant. The leaves on the lower one third to one half are removed. A high percentage of the cuttings should root easily.

Softwood cuttings
These are prepared from soft, succulent, new growth of woody plants (rose or woodbine) just as it begins to harden (mature). The soft shoots are quite tender and should not be allowed to dry out. The time to get this new growth is around May and June.

Semi-hardwood cuttings
These cuttings are obtained in mid July to autumn. They will have partially mature wood on the current seasons growth. The wood is quite firm and the leaves are full sized. Many broadleaf evergreen shrubs are propagated this way.

Hardwood cuttings
These are taken from dormant, mature stems in autumn, winter and spring. The wood is firm and does not bend easily. Hardwood cuttings can be used for many evergreen plants as well as deciduous plants

TAKING CUTTINGS
Take cuttings in the early morning if possible, because the plant is fully turgid (full of water) the cuttings can be between 4-6 inches long (8-12cm) cutting just below a node on the stem. The lower third of the leaves can be removed. Large leaves on the cuttings could be cut in half to prevent too much water loss. Some people recommend a rooting hormone powder to increase the chances of the cuttings rooting. I have found very little evidence to prove the powder works except on Potentillas where it does seem to improve the chances of the cuttings taken. Use sterile potting compost that is low in nutrients, this helps the roots form faster as they search for food. One part peat compost to one part sand is a good mix. Push the cuttings in a third to half the length making sure they are the right way up. Water in and cover with plastic, being sure to avoid direct sunlight.

The newly rooted plants can be transplanted into pots to establish outdoors before they are put into their final position in the garden.

Horticultural.