Plants from Cuttings
I prefer to grow most native plants from seed rather than from cuttings. However, there are some advantages to growing plants from cuttings. These include: (1) seeds might not be available or limited in amount, (2) cuttings preserve the unique genetic identity of the parent plant, (3) cuttings often mature sexually (i.e., produce flowers and fruits) quicker than plants grown from seed, and (4) for some species, rooting cuttings is much easier or faster than growing the plants from seed. I use three methods for propagating native plants from cuttings: (1) placing cuttings in a clear container, (2) placing cuttings in a mist chamber, (3) placing cuttings directly into the ground using a technique I call the DG-method.
Preparing and Potting the Cutting
Try to collect cuttings only from plants in good health and vigor. Plants with wilted leaves because of drought or plants showing other signs of stress (e.g., few leaves), generally, do not yield cuttings that root well or easily. Cuttings from cultivated plants often root better than those from wild plants. Whenever possible, I collect a cutting about one foot long. This allows me to trim and shorten the cutting later when potting. In the case of trees or shrubs, avoid cutting horizontal or descending branches because these will sometimes yield a plant that does not exhibit a natural shape (e.g., a sprawling shrub instead of an upright tree). Immediately place the cutting in a moisture-tight and rigid container containing a small amount of water to avoid wilting and damage.
Back at home or the nursery, prepare the pots first and then the cuttings. I generally use square or round pots instead of dibble tubes for my cuttings; I’m not exactly sure why except that I find them more convenient to stand upright and they visually remind me that the plant was grown from a cutting. Different horticulturists prefer different rooting media. I fill my pots with a 1:1 mixture of perlite and vermiculite or, for particularly easy to root cuttings, a 1:1:1 mixture of perlite, vermiculite and peat moss. This second mix is normally adequate for good growth until I plant out the plant; cuttings propagated in the first mix usually need to be repotted to another media mixture to get good growth after rooting.
Wash the cuttings thoroughly with clean water. (I sometimes add a small amount of dishwashing liquid). While washing, look carefully for any insects and eliminate them. Remove any flowers or flower buds (they will divert energy away from developing roots) and any severely damaged leaves. Then, remove all the lower leaves until only the top 3-4 inches of the cutting has attached leaves. Recut the bottom of the cutting directly through a node about 6-9 inches from the growing tip using a razorblade for a clean, undamaged cut. Treat the bottom of the cutting with a rooting hormone. I typically use a 1:10 dilution of Dip’nGrow® but all the various brands of rooting hormone, powder, gel and liquid, seem to do the job. Gently place the cutting in a pre-made hole in the potting media (i.e., do not push the cutting down through the potting media since this could injure the freshly-made cut) so that at least two nodes are below the surface of the media and there still exists 1-3 inches of media between the bottom of the cutting and the bottom of the pot (i.e., do not place the bottom of the cutting at the very bottom of the pot). Some native plant growers will make multiple cuttings from one collected stem. I prefer not to do this for two reasons: (1) sometimes the stem-tip will produce hormones that aid in root formation, and (2) generally, a cutting with an intact stem-tip will yield an immediately more attractive plant.