The method of propagating summer cuttings to grow new plants involves collecting softwood or semi-hardwood stem sections and placing them in an environment that stimulates root growth. Make softwood stem cuts during the months of May, June and July, when the shoots are tender. Make semi-hardwood stem cuts during the months of July, August and September, when the stems are mature and firm. Softwoods sections have the benefit of rooting quickly but are tender and dry out quickly when not monitored for moisture levels.
Cut a 6-inch softwood or semi-hardwood section of stem from the upper portion of plant where there is new growth. Place cut stems in a plastic bag with a damp towel to prevent moisture loss.
Make a well-draining rooting medium by mixing equal parts sterile peat moss, course sand and perlite. Pour enough water into the mixture to moisten it. Fill a clean rooting tray with the soil mixture.
Cut all leaves off of the lower one-third of the softwood stem section. Pour a small amount of powdered rooting hormone onto a piece of waxed paper to prevent cross contamination. Dip the softwood or semi-hardwood cutting into the rooting hormone.
Stick the leafless portion of the softwood or semi-hardwood stem into the rooting tray filled with the moist soil mixture. Firm the soil mixture around the stem to hold it in place. Stick additional stems in the rooting tray so the leaves do not touch.
Cover the rooting tray that holds the softwood or semi-hardwood cuttings with a clear plastic bag. Close the bag and seal it with a rubber band or twist tie to create a humid environment for the stems. Place the tray in a warm area with an indirect light source.
Open the plastic cover once daily to introduce fresh air. Mist the softwood and semi-hardwood stems lightly with water and close the bag covering. Continue to mist the cuttings daily until the presence of root growth.
Pull on the softwood stems after three weeks of growth and the semi-hardwood stems after six weeks of growth to see if there is resistance from the presence of roots. Monitor root growth by gently removing the soil to verify the root length.
Transplant softwood and semi-hardwood stems to individual growing containers once the root growth reaches 1 inch in length. Grow the stems indoors in a bright, filtered sunlight area.