Protea is a distinctive plant with strong, thick stems and shiny, dark green leaves and a few large, colorful flowers in colors ranging from ivory to bright red. Most protea will produce 10 or fewer flowers each season, but occasionally a plant will send out up to 40 blooms. Protea thrives in poor soil and is often the first plant to emerge after a fire. Taking stem cuttings from protea can be challenging because of the thickness of the stems, but it’s the best way to propagate this unusual plant.
Fill a planting container with good-quality commercial potting soil, or a mixture of half sand and half peat moss. If you’re planting one or two cuttings, a 2- to 3-inch pot is big enough, but if you plan to root several cuttings, you’ll need a larger pot. Any type pot with good drainage will do.
Locate a healthy shoot growing from the protea’s main stem, and snip off a piece of stem about 3 to 4 inches long. Make the cut below a leaf node, which is a bump where a new leaf will emerge from the stem. Remove the stems from the lower half of the cutting.
Make a half-inch wound on the side of the cut end of the stem by peeling off a thin layer of the outer skin. This is where the new growth will occur. Dip the end of the stem in rooting hormone and hold it there for about four seconds.
Create a hole in the potting soil with a pencil, and plant the cutting up to the base of the remaining leaves. Don’t let the leaves touch the soil, and don't rub off too much of the rooting hormone as you plant.
Mist the soil with a spray bottle until the soil is damp clear through. Put the cutting in a plastic bag, and put a few stakes in the soil to hold the plastic away from the cutting. Seal the plastic bag and put the container in bright light, where the temperature stays constantly around 75 degrees. Avoid putting the container in a window, because the magnified sun will burn the cutting.
Loosen the plastic and spray the soil whenever it appears to be drying out. Although humidity is crucial, don’t overdo, because overwatering can cause rot and disease.
Check the bottom of the container for the appearance of roots after about a month. If roots haven’t appeared, check the container every two weeks. It can take several weeks for a protea to root.
Remove the protea from the plastic bag once it has roots at least an inch long. The transition from a humid environment to a drier one should be made gradually. The first few days, just open the bag slightly, then gradually open it up more. After at least a week of gradual acclimation, remove the container from the bag.
Continue to keep the soil damp until the following spring, when it will be ready to plant outside. Repot the plant in a larger container if the roots get too crowded or the plant outgrows its pot.