Propagating flowers get you lots of additional plants from those you already have in your garden. Flowers can be propagated, or reproduced, through seeds, root cuttings, grafting, leaf divisions and stem cuttings. Propagating by cuttings results in plants that are identical to the parent plant, because no genetic material has been exchanged with another plant through pollination.
Select a strong healthy plant as the parent of the cuttings. The flower color of the parent plant will be the color of the flowers of the cuttings when they eventually bloom. Geraniums, roses, bougainvillea and hibiscus are examples of flowers that can be propagated by stem cuttings.
Water the plant 24 hours before taking cuttings, so it's well hydrated.
Poke two holes in the bottom of the paper cup with the pencil. Fill the paper cups with fresh new potting soil. Label the cups with the type of plant. Water the soil until it is wet and the water drains through the bottom of the cup.
Poke the pencil into the soil to make a 2 inch deep hole.
Cut the stem about 4 inches from the tip, right below a leaf node. Remove those leaves and any other leaves from the bottom 2 inches of the stem. At least two leaves should remain on the stem. Wipe the knife with rubbing alcohol to disinfect it between cuttings.
Place about a teaspoon of rooting hormone in a paper cup without holes. Dip the end of the cut stem into the rooting hormone. Tap off excess. Too much hormone prohibits root growth.
Place the cutting into the hole and firm the soil around it so the bottom of the stem makes contact with the soil.
Place the cup with the cutting into a plastic twist tie baggie or zip lock bag and seal. Place all the cups on a tray covered with black plastic. The black plastic absorbs heat, which encourages root formation.
Put the tray outside in dappled shade if it's warm. If it's too cool, below 70 degrees, keep the cuttings in the house in bright light.
Tug gently on the cutting after about a week. If it has rooted it will resist the tugging. Rooting can happen in a few days or up to a month.