How to Propagate Plants from Cuttings
When people speak of propagating plants, they usually mean taking cuttings — using pieces of stems, roots, and leaves to start new plants. Softwood stem cuttings, taken from spring until midsummer, root the quickest. During this time, plants are actively growing, and the stems are succulent and flexible.
Here’s how to take a softwood stem cutting:
Cut a 4- to 5-inch-long (10 to 12 cm) stem (or side shoot) just below a leaf, and remove all but two or three leaves at the top.
Make sure you use a sharp knife to minimize damage.
Dip the cut end into rooting hormone.
Rooting hormone is a powder or liquid containing growth hormones that stimulate root growth on cuttings. Some also contain a fungicide to control root rot. Local nurseries or garden centers carry the product.
Insert the cutting into a box or container, filled with about 3 inches (8 cm) of moistened pure builder’s sand, vermiculite, or perlite.
The ideal container should have drainage holes.
Slip the container into a self-sealing plastic bag.
Prop up the bag with something like toothpicks or short twigs so that the plastic doesn’t touch the leaves. Seal the bag to minimize water loss, but open it occasionally to let in fresh air.
Place the covered container in indirect light.
Easy-to root perennials include begonia, candytuft, chrysanthemum, carnations or pinks (Dianthus), geraniums (Pelargonium), penstemon, phlox, sage, sedum. Woody plants that you can root include bougainvillea, fuchsia, gardenia, heather, honeysuckle, ivy, pyracantha, star jasmine, and willow.
When the cuttings are well rooted (4 to 8 weeks, for most plants) and are putting on new growth, transplant them into individual containers of potting soil.
As they continue to grow, gradually expose them to more light. When the plants are well established in the pots and continue to put on top growth, harden them off (acclimate them to your weather conditions) and plant them in their permanent garden location.
To harden off new plants, gradually move them to more extreme temperatures and sunlight. Moving them from the porch to outside in partial sun and finally to full sun over a week’s time should do the trick