Any plant that can be propagated by cuttings can be propagated by layering. Layering is really just a cutting still attached to the plant until it has rooted on its own. Plants vary considerably, however, in how easy they are to root.

Commercial vegetative production uses cuttings or grafting. Layering is impractical on a large scale, requires a branch close to the ground and results in a highly noticeable bend in the new plant. All in all, unless you have one or two plants you'd like to layer, cuttings are a better way to go.

Thanks for the reply, Mainegrower. I am totally new to propagation, so I thought trying a few layered shrubs would be the easiest way to start. I have noticed some of my shrubs doing this themselves -- rooting into the mulch -- so I figured it couldn't be too hard, and I'd give it a go. Maybe success in layering will inspire me to start doing cuttings.

My shrubs that have layered themselves include Clethra alnifolia and Viburnum tomentosum (doublefile). The ones I'd like to do are lilac, Fothergilla major, Korean allspice viburnum, and inkberry (Ilex glabra). Would any of these present problems?

jayco: I think your success would probaby be greater with cuttings than with layering. Keeping the area around the part of the layer where you want roots to form is not easy in the summer. The plants you want to multiple should not present any great difficulties. There is a lot of information about cutting propagation online and in most complete gardening books.

Now, I've got to ask if you are perhaps confusing layering with suckering. The two plants you mention as having rooted themselves into the mulch naturally produce root suckers, especially the clethra. These can be carefully dug, potted and planted out when they're big enough. Layering involves bending a branch (or using one that's already close to the ground), wounding it, pegging it down and covering with a moisture retaining soil mix, and waiting until there are enough roots to allow the new plant to grow on its own. Sometimes plants do naturally layer themselves, but generally not ones that normally grow upright.

Okay, I will take your advice and read about using cuttings. It somehow seemed more difficult to me than layering, but I know zip about this and am sure you know more!

I do know the difference between a sucker and a layered branch rooting itself. One of my clethras was mis-shapen when I purchases it (75% off so what the heck), and some of its branches are very low and always get buried in the mulch. One of these rooted, which I discovered when weeding and applying new mulch. Pretty much the same for a doublefile viburnum, which has some very low branches. Both are in wettish areas as well, which I guess must help.

Anyway I will read up about doing cuttings; thanks for the advice.