|What is the best method of propagating stewartia pseudocamellia that you know of? thanks|
|Softwood cuttings are the most successful of all the propagating techniques. The trickiest part of propagating shrubs from softwood cuttings is knowing when a shrub's stems are ready to be cut. Softwood, the section of a shrub's stem that's neither brand new nor fully mature, is the stage of growth on a deciduous woody plant that is best suited for rooting The newer, green growth that lies at the end of the stem will rot before roots are produced, and the older, more woody growth at the base of the stem has a harder time putting out roots.
Softwood cuttings can be taken from most deciduous shrubs in July and early August. I determine a stem's maturity by taking it in my hand and bending it. If the stem breaks with a characteristic snapping sound, it is in the softwood stage and ready to be harvested as a cutting. If the stem is still too green, it will bend but not break. If the stem is entering the woody stage, it won't bend at all.
The best time to take cuttings is early in the day, when shoots are fully hydrated. Lateral shoots, or those that grow from a leader, make the best cuttings. I avoid weak, thin shoots, as well as overly thick, heavy ones. As soon as I take a cutting, I nestle it into a plastic basin that I've filled with damp paper towels. The towels will keep my cuttings moist and cool until I'm ready to head back inside and pot them up. They also shade my cuttings from the sun. Exposure to direct sunlight, even for only a few minutes, can cause irreparable damage. I also avoid taking cuttings on hot days, when plants may be wilting.Keep cutting short to conserve energy.
A cutting's size is also something to consider. I like my cuttings to contain at least two sets of leaves. I use pruning shears to cut the stem from the shrub at about one-inch below the second leaf node. Since the length between leaf nodes differs from plant to plant, the size of a cutting, using this rule of measurement, will vary. The average cutting should measure between 3 and 5 inches.
To prepare my cuttings for rooting, I remove the lower set of leaves to open up wounds on the shoot. It is at these wounded sites that rooting will occur.
Provide good drainage and air in the rooting compost.
Insert the stem into a six-pack or seedling tray filled with a moistened mixture of perlite and peat mix. The potting mixture we use is 60 percent perlite and 40 percent peat mix. This mix provides the good drainage and maximum aeration that new roots need. Cuttings placed into a mix that holds moisture is apt to rot before rooting occurs.
Once the cuttings are inserted into the soil, I trim the remaining leaves in half to cut down on transpiration loss. These leaves are still performing photosynthesis, even though there are no roots to draw moisture out of the soil. Next I soak the cuttings and the compost with a watering can with a fine head and allow the excess water to drain away for 10 mins.
Finally, I place the tray into a milky white plastic bag and seal the end to create a small humid microclimate, which will create the conditions needed for rooting to take place. I then place the tray or pot on a sheltered windowsill away from direct sunlight.
Best wishes with your propagation project!