Most of you are probably familiar with my friend David Culp’s book The Layered Garden that describes masterful techniques for succession planting. David’s guidance helps to ensure a garden space is always interesting in texture and/or color from season to season. There is another kind of layering too, and it’s a way to propagate our beloved plants.
Some plants layer on their own which makes them effective for erosion control and bank stabilization. Lonicera, Deutzia, Aronia ‘Ground Hug’, Stephanandra, and Symphoricarpos are all good choices for this.
Other plants can be layered with some effort like Aesculus, Hydrangeas and many others. Air layering is a technique for tricking a branch into rooting when it’s not in contact with the soil. First you scratch a stem on the plant to expose the cambium. Then you mix some moist potting soil and rooting hormone together in plastic wrap and mold it around the scratched stem, sealing the plastic wrap around the stem to contain the moisture and maximize the stem to soil contact. To eliminate exposure to light, wrap the plastic soil packet with foil. Then wait.
While the foil package may look a bit suspect to garden visitors, hopefully it will reward you with a clone of your favorite plant. Just like you would check a foil wrapped baked potato in the oven for doneness, after a few weeks unwrap the package to see if roots have developed. If you don’t see roots, seal up the package and check again in a few more weeks. Sometimes the process can take months.
If you are interested in an easier form of layering, take a branch low to the ground on your favorite shrub and place it in contact with the soil. Bury it slightly in the soil and hold it in place with a landscape pin or a rock. With luck you’ll see roots after a few weeks. Sometimes as we work in other people’s gardens, we see layering occur when lower branches have been inadvertently trapped by over-mulching.
Once you see roots on a layered plant, you can cut the branch off the plant and place the rooted cutting in a container to grow it on for a bit until you are ready to place it in the garden or gift it to a friend. I hope you’ll try layering as a technique to share plants or create more of those you want to reproduce. The process is economical, fun and rewarding.