There are many ways to propagate shrubs in order to raise new plants: taking cuttings, sowing seeds, layering, division and grafting. Taking cuttings is a simple way of propagating many shrubs and is mainly useful for cultivars, hybrids and spores. Layering and division are also used to some shrubs. Sowing seeds is an inexpensive but slow process. Grafting require some experience and skill than any other methods but for some shrubs this is the most suitable method.
Propagations by taking cuttings can be done with different type of cuttings: softwood cuttings - suitable for deciduous shrubs, taken in spring; greenwood cuttings - also suitable for deciduous shrubs, can be of two types: nodal cuttings or heel cuttings, taken in late spring or early summer; semi-ripe cuttings - suitable for evergreen and some deciduous shrubs, can be of two types: mallet cuttings or leaf-bud cuttings, taken from mid to late summer or early autumn; hardwood cuttings - suitable for many deciduous and some evergreen shrubs, taken from late autumn to mid winter; root cuttings - only some shrubs, taken in mid to late winter.
Propagation by layering is a method of propagating shrubs whereby a stem is encouraged to develop roots before being removed from the parent plant. There are few different type of layering: simple layering - suitable for many deciduous and evergreen shrubs, done in autumn or spring; air layering - suitable for shrubs with branches that are difficult to lower to the ground level, done in spring; tip layering - suitable only for few shrubs, done in spring; dropping - used to raise dwarf shrubs, done in the dormant season; stooling - used for some deciduous shrubs from engrafted plants, done in spring; french layering - used to increase the stock of deciduous shrubs, done in the dormant season.
Propagation by division is a simple way of increasing shrubs that produce suckers.
Raising shrubs from seeds is a simple and economical way to propagate shrubs. Collect and clean ripe seeds or buy some and store them in dry places before sowing. The seeds of some shrubs have a form of dormancy that prevent them to germinate in adverse conditions. Broke this dormancy by scarification or stratification. Sow seeds of hardy shrubs in a cold frame in autumn and in open ground the ones tha tdo not need daily attention.
Propagating by grafting is one of the most important way to propagate shrubs that are difficult to root or are unlikely to come true from seeds. There are three methods used for this technique: saddle grafting - used to propagate evergreen rhododendron species, done in late winter or very early spring; spliced side-veneer grafting - used to a large variety of evergreen and deciduous shrubs, can be done in summer or winter; apical-wedge grafting - suitable for some species of shrubs, done in mid winter.
