Most plants can be propagated from cuttings however, some plants are quite difficult to persuade to grow roots, whilst others may take an inordinate length of time (years) to “strike”. Do not let such problems, either real or imagined, prevent you from trying. Propagating mix: Generally, sand, or vermiculite, or a mix of the two will be satisfactory. Even compost and/or composted wood-chips have been used with success.
Soft-Tip Cuttings: Usually taken in Spring. Very few fruit trees are propagated by this method, but generally anything in the Solanum group, such as Pepinos and Tamarillos will be fine. Take a reasonably substantial length (normally not less than 10cm) from the growing tip of the branch [twig]. Make the cut directly below a growth-bud. Remove all but the very top leaves, and reduce the size of the leaves which are left on, this reduces evaporation-loss of liquid from your cutting. Plant your cuttings in the propagating-mix to ¾ of its length. A rooting-hormone powder may be used, but is generally not necessary. Do not allow the propagating mix to dry out, and mist over the cuttings daily. Some method of supplying bottom-heat would be an advantage, such as sitting the container with the cuttings in the top of a hot-working compost heap. The cuttings may be potted-up as soon as the roots appear, often after only 3 weeks. Problems: Fungal infections resulting from the moist, humid conditions may require treatment with a fungicide.
Semi-Mature (Tip) Cuttings: Usually taken in Autumn. Citrus, Feijoa, and other evergreens can be propagated by this method. Note that many Citrus are prone to soil-born diseases, and therefore only resistant varieties such as Poncirus trifoliata and citrange should be propagated by cuttings, usually for use as rootstocks. Take a reasonably substantial length (normally not less than 10cm) from the tip of a branch [twig] that has ceased its seasonal growth but is still green and soft. Make the cut directly below a growth-bud, or, if the propagating-wood is short enough, tear it off the main branch, leaving a “heel” of older wood attached. Remove all but the very top leaves, and reduce the size of those leaves, to reduce evaporation. Plant the cutting in the propagating mix to ¾ of its length. Do not allow the propagating mix to dry out. Some method of supplying bottom-heat is frequently an advantage. Commercial growers often heat the benches upon which the cutting trays are placed. The little plants should be rooted and ready to pot-up in Spring. Problems: Fungal infections are the worst danger, but watch out for snails and slugs.
Hardwood (Mature) Cuttings: Usually taken in late Autumn or Winter. Deciduous fruit-trees can usually be grown by this method, but evergreens are also worth trying. Take a substantial length (normally not less than 15 cms long, or less than ½ cm thick). Make a slanting cut just above the terminal growth-bud, just as if you were pruning. Make a horizontal cut immediately below the bottom growth-bud on the cutting. Now you know which way is up, and you won’t plant the cutting upside-down! Remove any leaves. A slight vertical slit in the bottom of the cutting may increase the callous (rooting) area. Plant the cutting in the potting-mix to at least ¾ of its length (some propagators only leave the top bud above the surface). Rooting-hormone is generally a waste of money for hardwood cuttings. Do not allow the propagating mix to dry out. Some form of bottom-heat may help things along. The plants should be ready to pot-up by the following Winter. Some plants can take a very long time to produce roots: just put them back in and wait for another year!