One sage plant can give you several more, for free. All you need is a sharp knife and a little patience. A cutting grows into a usable plant faster than a seed does. It also matches the parent plant exactly, so you avoid the variation seed can bring. The thing that matters most is timing: soft, actively growing stems root fastest.
What you need
- A sharp, clean knife or florist's scissors
- A healthy sage plant with soft, non-flowering new growth
- Small pots, 3 inches (8 cm) across, or a glass of water
- Free-draining, gritty compost (add horticultural grit or perlite if yours is heavy)
- A bright spot out of strong direct sun
- Rooting hormone powder or gel, optional but it can help
When to take cuttings
You are aiming for a softwood cutting: one taken from soft, leafy stem growth rather than older wood. Take cuttings once new shoots carry a few inches (several centimeters) of this soft growth. Do this before any stem feels woody or stiff. As a rough guide, wait until night temperatures reliably sit above about 50°F (10°C). This applies whichever part of the growing season it falls in where you garden. Soft, vigorous growth roots more reliably than old and woody growth. Woody growth often fails to root at all. If your plant is still recovering from a hard winter, wait for a flush of fresh growth first.
Step 1: Choose a healthy, non-flowering shoot
Look over your plant and pick out several young shoots. Morning is often the best time to do this, since the plant holds the most moisture then. Choose ones with no flower buds showing. A non-flowering shoot puts its energy into leaves, not blooms. That means it roots more readily. Pick stems that snap cleanly rather than bend. A clean snap is a sign the growth is soft rather than woody. Avoid a shoot that looks damaged, pale or eaten by pests. A struggling cutting like this is unlikely to root well. Take several cuttings at once if you can, because not every one succeeds.
Step 2: Take the cutting
Cut a length of stem 3 to 4 inches (8 to 10 cm) long. Make the cut just below a leaf joint, known as a node. Roots form most readily there. Use a clean, sharp blade so you leave a neat cut rather than a crushed one. A ragged cut heals more slowly and lets rot take hold more easily. Strip the leaves from the lower half of the stem. Leave just two or three pairs of leaves at the tip. Pinch off any flower buds, so the cutting puts its energy into rooting instead. Work quickly, and keep the cuttings out of direct sun while you finish taking the rest.
Step 3: Root the cutting in water or gritty compost
You can root sage cuttings in water or straight into compost, and both work well. For water rooting, stand the stripped stems in a glass with the lower node submerged. Change the water every few days to keep it fresh. For compost rooting, dip the cut end in rooting hormone if you are using it. Then push the stem about an inch (2.5 cm) into free-draining, gritty compost and firm it in gently. Covering the pot loosely with a clear bag helps the cutting hold humidity while it roots. Water compost-rooted cuttings well after planting. After that, keep the compost just moist rather than wet. A waterlogged compost rots stems before they root.
Step 4: Pot on once rooted
Water-rooted cuttings are usually ready once the roots reach about an inch (2.5 cm) long. This normally takes a few weeks. Compost-rooted cuttings are ready once you feel gentle resistance when you tug a stem. That resistance means roots have formed and gripped the compost. Move each cutting into its own small pot of ordinary, free-draining potting compost. Bury the stem to the same depth it was rooted at, then firm the compost gently around it. Water well to settle it in, then keep the young plant somewhere bright but out of harsh midday sun for a week or two.
Step 5: Harden off the young plant
Before a young sage plant moves outdoors for good, it needs to harden off. This means getting a plant used to outdoor conditions gradually. Wind, sun and temperature swings then do not shock it. Start by standing the pot outside for an hour or two on a mild, still day. Bring it back in afterward. Over a week or two, increase the time it spends outside each day. Aim to have it stay out overnight without trouble by the end. Bring it back under cover if a late frost is forecast, since a hardening-off plant is more vulnerable to cold than an established one.
Step 6: Protect young plants through their first winter
A young sage plant is more tender than a mature one, so its first winter needs extra care. Grow it in a container where you can. Move that container against a sheltered wall, or into an unheated greenhouse or porch. Do this once cold weather sets in. Keep the compost on the dry side over winter. Cold, wet roots are a far greater risk to sage than cold air alone. If the plant is in open ground instead, mulch around its base without letting mulch touch the stem. Cover it with horticultural fleece during hard frosts. Hold back on feeding and heavy watering once growth slows. Soft, late growth is the most frost-prone of all.
Common problems
Cutting turns black and collapses
This is rot, usually caused by stagnant water or waterlogged compost. In water, change it more often and keep only the very base of the stem submerged. In compost, let the surface dry out slightly between waterings. Check the pot or tray drains freely, rather than sitting in a saucer of water.
Cutting wilts and does not recover
A wilting cutting has lost more moisture through its leaves than its unrooted stem can replace. Trim back any large remaining leaves to reduce that water loss. Keep the cutting out of direct sun and drafts. Give it time; new growth is the first sign that rooting has started.
No roots appear after several weeks
Cold conditions slow rooting down considerably. Move cuttings somewhere warmer, ideally around 60 to 70°F (16 to 21°C). Gently scratch the stem with a fingernail to check it. A stem that is still firm and green underneath is alive and worth keeping. A soft or brown stem has died and is best discarded.
Leaves turn yellow and drop after potting on
Some leaf loss after potting on is normal, and it usually settles within a week or two. Leaves that keep yellowing and dropping more often point to overwatering. Let the compost dry out slightly between waterings, and make sure the pot has drainage holes.
Young plant collapses over winter
This is almost always waterlogging rather than cold alone. Move containers under cover if you have not already. Raise pots off the ground so they drain freely. Hold off on watering until the compost has dried out somewhat, even in a mild spell.
What to do next
Once a young plant has come through its first winter and starts putting on fresh growth, pinch out the growing tips. This encourages a bushier shape. From there it grows on like any established sage plant. Next year, you can take a fresh round of cuttings from it or from its parent.