Rooting Cuttings in Water: What Works

Water rooting works for soft-stemmed, actively growing plants with nodes (pothos, basil, mint, tomato side-shoots), for a jade plant leaf, and for spider plant plantlets. It doesn't suit dormant woody hardwood cuttings, which root in soil with rooting hormone, and pelargoniums and fuchsias are conventionally rooted in compost. Pot a rooted cutting once the roots are a few centimetres long: the commonest failure isn't the rooting but leaving it in the jar for months. There's a jar on most windowsills that has been there longer than anyone meant. A pothos cutting went in last spring, roots showed within a couple of weeks, and six months on they are a tangled white knot against the glass and the plant has never seen soil.

Which cuttings take to water

Water rooting is really three methods, depending on the part of the plant. The most familiar is a stem cutting with a node, the small swelling where a leaf joins the stem and where roots form. Pothos (Epipremnum) is the classic: stem cuttings stood in a glass of water in a bright place until roots appear, then potted up, are a standard method (RHS), alongside layeringPropagating a new plant by pinning a low, flexible stem into the soil while still attached to the parent, so it roots before being cut free. Full definition → stems into compost. Heptapleurum (umbrella tree) roots the same way. For basil, snip a non-flowering shoot just below a leaf, remove the lower leaves, pinch outRemoving the soft growing tip of a stem to stop upward growth and make the plant branch out sideways instead. Full definition → the tip and stand it in a jar of water, where it quickly forms roots and can go into peat-freeCompost made without peat, which is harvested from a slow-forming, carbon-storing wetland habitat that peat extraction damages. Full definition → compost after a few weeks (basil also roots directly in compost). Mint softwood cuttings root readily in a jar of water, as well as by divisionPropagating a clump-forming perennial by digging it up and splitting it into several smaller pieces, each with roots and shoots attached. Full definition → and rhizome.

A second route is a leaf cutting: a whole leaf of Crassula (jade plant) either rests on compost or stands in a small amount of water, where it develops roots. A third involves no cut at all: spider plant (Chlorophytum) makes plantlets on runnersLong, trailing stems a plant sends out that root where they touch soil, producing a genetically identical new plant for free. Full definition → that can be snapped off and floated on a shallow plate of water, or rooted in soil.

Tomato side-shoots are a less obvious entry. On cordonA fruit tree or bush trained as a single main stem with short fruiting side-spurs, usually grown at an angle against a wall, fence or wire. Full definition → (single-stem, staked) varieties the shoots that grow at the joint between leaf and main stem are pinched out weekly, and a healthy one 10 to 20cm long can go into a glass of water on a bright windowsill instead of the compost heap, rooting in three to four weeks as a rule. Tomato guidance covers removing side-shoots but not rooting them, so this rests on grower practice rather than a trial. Bush tomatoes don't produce them in the same way and need none of this. Do it early in the season, while a late plant still has summer to crop; a shoot pinched out in August is much less useful.

Not everything that looks like a candidate is one. Hardwood cuttings, the classic method for willow, roses, currants, gooseberries, forsythia and viburnum, use dormant woody stems taken in the cool months and are rooted in soil or a soil and grit mix, with rooting hormone, not water. Pelargoniums can be propagated from softwood cuttings from spring to autumn, and fuchsia likewise, both rooted in compost, with no mention of water. Water may well work for them, and plenty of gardeners try it, but it isn't the documented, reliable route the way it is for pothos, basil or mint. Coleus is a middle case: it has the same soft stem and frequent nodes as the water-rooters, but its RHS entry says only "by seed or cuttings", so there is no documented water or compost answer.

Willow has a folk reputation as the plant that roots in anything, but its documented methods are softwood cuttings in early summer or hardwood cuttings in winter, rooted in soil or a pot of compost, so that is the reliable route even though a willow whip in a bucket of water might take too.

Why some cuttings rot

A node on a leafy, actively growing stem, or a fleshy leaf like Crassula's, is primed to make roots quickly given water, oxygen and light. A dormant, woody hardwood cutting isn't, which is why it is paired with rooting hormone and a free-drainingSoil that lets water pass through quickly rather than pooling, so roots aren't sitting in wet ground after rain. Full definition → soil or grit mix: without them, and without drainage, it sits wet and rots before it roots. Even softwood cuttings in compost carry a warning to check weekly for dead, rotting or diseased material, since soft tissue breaks down quickly in humid conditions. The same applies to a jar. If the water goes cloudy, slimy at the base or green with algae, tip it out and refresh it. Fresh water also re-oxygenates the jar, since submerged roots use up the oxygen dissolved in still water, and stale water is part of why roots left unchanged can stall or rot.

Why water-rooted cuttings struggle after potting

Roots left in water for months were built for water: soft, and not adapted to pushing through the resistance and patchier moisture of soil. Moving to a pot is a real adjustment, and new roots are vulnerable to rotting before they establish in the new medium, so go easy on watering at first. There is no need to feed a cutting still rooting in plain water, because it goes into nutrient-bearing compost within weeks, and a feed only becomes worth starting once it is potted and growing on. Potting once roots reach a modest length makes the transition easier than waiting for a solid tangle, since a smaller root system has less to lose. Firm compost around the roots in a properly sized pot, not an oversized one, and give a fortnight of light, consistent watering and gentler light while they settle.

Cutting to potted plant

Take the cutting. For most houseplants take a stem about 8 to 10cm long, cut just below a leaf joint. Strip the lower leaves so nothing sits below the waterline (submerged foliage rots and fouls the water), and keep two or three leaves at the top. Take two or three cuttings if the plant can spare them, since not every one takes.

The jar and the water. Any clear glass works, and lets you check roots without disturbing the cutting, though it also lets in enough light to grow algae after several weeks, so rinse and refresh if that starts. Keep the water level just below the remaining leaves, submerging at least one node, in a bright spot but not direct sun, which can scorch a cutting that has no roots to draw on. For pothos, rainwater or filtered water is better than hard tap water, because lime works against the slightly acid compost it prefers once potted (RHS); tap water suits the others. Much Scottish tap water is soft, so the hard-water caution matters less here. Pothos is toxic, and it is worth checking any houseplant for pet toxicity before leaving cuttings where pets can reach them. Pothos is toxic, so wear gloves when handling it and keep it away from children and pets.

Houseplant cuttings generally root in 3 to 4 weeks, in water or in a 50:50 mix of peat-free compost and perlite (RHS). Pot on once the roots reach a few centimetres and, ideally, new top growth has started: firm the compost gently, water in, then keep it lightly moist and out of strong sun for the first week or two.

Does Scotland's climate matter?

Mostly not: rooting in a jar is an indoor technique, and the room's warmth matters more than the weather outside. Light is the exception. Scottish winter daylight is shorter and duller, and even the sunniest coasts, Fife and East Lothian, average under 1,500 hours of sunshine a year, falling below 1,100 hours over the Grampians, against over 1,750 on the south coast of England. A cutting on a dim winter windowsill is likelier to put on weak, pale, stretched growth, so a consistently bright spot matters more here, though it isn't a reason to avoid winter cuttings.

The other difference is timing. Cuttings of tender bedding such as pelargoniums and fuchsias, taken in late summer or autumn to carry plants through winter, are rooted in compost rather than water. Once hardened offGradually getting young plants raised indoors used to outdoor conditions over 7–14 days before planting out, so cold, wind and direct sun don't shock or damage them. Full definition →, pelargoniums are not usually safe to plant out before the end of May in most of the UK, and not until early to mid June in Scotland (RHS), so a cutting nursed through a Scottish winter needs those extra weeks in its pot somewhere frost-free. See Scotland frost dates. Full guides: mint, basil and tomatoes.

Common questions

For the specific crops named here, see our full growing guides for mint, basil and tomatoes.

Sources