"How do I get a start of that pink one?" my neighbor asked, leaning over the fence at the fragrant shrub by my porch. I pulled out my snips, cut a few soft green shoots, and pushed them into a pot of damp mix in the shade. Most had rooted within a month. That is how forgiving propagating summersweet is. You can do it three ways: with cuttings, from seed, or by division.
Cuttings are the route I reach for first, and the one I always recommend to anyone starting out. Take summersweet cuttings in early summer, while the new shoots are still soft and bend without snapping. Each one wants to be about four to six inches long. Strip the lower leaves off the bottom half, then sink the bare end into a pot of moist potting mix. Firm the mix around the stem so it stands up on its own.
Here is the part that makes this shrub a joy. Early softwood cuttings root at roughly 90% to 100% in about four weeks, and they do it without any rooting hormone. You can skip the powder you would need for tougher plants. I have never bothered with it on early cuttings, and they still take. Keep the pot in a humid, shaded spot so the leaves stay perky while new roots form below. A clear plastic bag over the top traps moisture and works like a tiny greenhouse.
Snip soft new shoots that are four to six inches long before the stems turn woody.
Pull off the lower leaves and press the bare end into a pot of damp, well-drained mix.
Set the pot in shade and mist it so the cuttings stay moist while roots grow in about four weeks.
Growing summersweet from seed takes more patience, but it costs you nothing. The brown capsules ripen in fall and hang on the plant through winter, so you can gather them on a dry day. Snap off a few capsules, crumble them over a tray of mix, and barely cover the tiny seeds. The seed needs no cold stratification, so you skip the long chill that many native plants demand. Keep the tray warm and moist, and the seedlings will push up on their own.
Seed has one quirk worth knowing before you commit. The young plants take a couple of seasons to reach a useful size, and they may not match a named variety like Ruby Spice. The seedlings can vary in flower color and habit, since each one is a little different from the parent. If you want that exact pink bloom, stick with cuttings or division instead. For a wild planting or a big batch of plants, seed is a cheap and easy way to fill a lot of space.
Division is the fastest path to a full-size plant. Summersweet spreads by root suckers, sending up fresh stems around the base of an old shrub. In early spring, dig down beside one of these shoots and slice it free with a sharp spade, keeping a clump of roots attached to the bottom. Plant it right where you want it and water it in well. You skip the long wait and get a ready-grown shrub the same day, which no cutting or seed can match.
Start with cuttings if you are new to propagating summersweet. They give you the highest and fastest success with the least fuss, and a shady windowsill is all the gear you need. Take your cuttings in early summer, keep them humid, and you will have rooted plants by late summer. Save division for when you want one big shrub fast, and try seed when you have time and want a whole crowd of them to share.
Read the full article: Summersweet Shrub: Care and Growing Guide
