Other Propagation Techniques
Some plants have root clumps that
can be easily divided by hand.
- Take root cuttings when stem cuttings are not possible. Some perennials, like Oriental poppies and horseradish, have clusters of foliage close to the ground without any stems at all. You can dig up a root and cut it into pieces that may sprout into new plants. With horseradish, you can cut off a side root in the fall and replant it for a new start in the spring. But root cuttings of most other perennials need more help than horseradish. Here's how to do it:
- Dig the root in early spring before shoots begin to emerge.
- Cut the roots into pieces an inch or two long.
- Lay them horizontally in a flat of well-drained propagating mix such as perlite or coarse sand. Cover lightly.
- Keep slightly moist but not wet (to prevent root rot) and watch for new sprouts to emerge.
- When the new plants are growing strongly, transplant them into individual containers or put them out in the garden.
- Easily divide daylilies, hostas, astilbes, or other clump-forming perennials with a sharp shovel. Just slice off an edge of the clump in spring or late summer. Uproot it and replant elsewhere. Keep the new division watered for at least several weeks or until it has regenerated lost roots.
- Divide a large perennial clump into small divisions to get many little plants fast. This is a quick and easy way to make enough plants for the big drifts, clumps, or ground covers that are so popular in landscaping today.
A mature bee balm clump might contain 50 rooted sprouts, each of which can be separated off and grown into a new plant. Other easily divided perennials include asters, daylilies, yarrow, phlox, lady's mantle, salvia, coreopsis, hardy geraniums, irises, mint, thyme, oregano, and winter savory. Here's how to make smaller divisions:
- In spring or late summer, dig up the entire perennial plant clump and wash soil off the roots with a hose.
- If dividing in late summer, cut back the foliage by half or more.
- Use your hands to break rooted sprouts into individual pieces. If roots are too hard to work apart by hand, slice them free with a knife or pruning shears. Each section should contain at least one leafy sprout and one healthy root.
- Replant very small divisions into pots of peat-based planting mix and tend them carefully until they get a little bigger. Larger divisions can go right back into the garden if kept moist until they become reestablished.
- Root the plantlets on spider plants and strawberry begonias, which grow from the parent plant on arching stems. These pretty plantlets have leaves but no roots, a condition that's easy to correct. Put a pot of peat-based potting mix beside the parent plant and set the plantlet in it. Firm the mix around the lower part of the plantlet and keep it moist. Once the plantlet roots, snip the stem and enjoy.
- Use layering to propagate hard-to-root shrubs like azaleas. Layering also works well with shrubs that have low-growing or creeping branches, like creeping rosemary. Layered stems develop roots while still connected to the mother plant, which helps nourish the rooting process.
- In spring, select a low, flexible branch that will bend down to the ground easily.
- Prepare well-drained but moisture-retentive soil where the stem will touch the ground.
- Nick the bark off the side of the stem that will touch the ground and remove the leaves near the nick. Dust the cut with rooting hormone.
- Cover the barren and nicked stem with soil. Top it with a rock or pin it in place with a stake or metal pin.
- The branch tip will become the new plant. If it is an upright grower, stake the tip upright to give it a good shape.
- Keep the rooting area moist for several months, until roots develop and become large enough to the support the new plant.
- Cut the new plant free from the parent branch and transplant it to a pot or new site in the garden.
Propagating plants is a great and economical solution to add even more beauty to your garden. Take heed of the tips outlined here, and you'll have more plants than you ever imagined!
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