Hydrangeas are generous flowering shrubs, and you can make more plants from a healthy one with a little patience. For many common shrubby hydrangeas, taking softwood cuttings in late spring or early summer is a practical home method. Semi-ripe cuttings later in summer and hardwood cuttings in winter are also possible, but young softwood shoots are often easiest for beginners to prepare.
The process is less complicated than it sounds. Choose a non-flowering stem, prepare a short section below a leaf joint, insert it into clean moist propagation compost and keep it sheltered while roots form.
Identify your hydrangea if possible
Mophead, lacecap, panicle and smooth hydrangeas can all be propagated, but their mature size and garden requirements differ. If you're taking cuttings from a friend's garden, ask for the cultivar name or take a photograph of the flowers.
The RHS notes that shrubby hydrangeas can take two to three years to start flowering when raised from cuttings. A successfully rooted plant is not expected to produce a full flower display immediately.
Climbing hydrangeas can also be propagated by cuttings and layering, but they grow differently and may take longer to flower. Label the plant rather than assuming every small rooted hydrangea should be placed in the same position.
Choose a healthy parent plant
Look for fresh shoots without flower buds, blemishes or visible pests. Non-flowering young growth generally roots more readily than a stem carrying a developing flowerhead.
Avoid material from a shrub with extensive fungal leaf spotting, blackened stems or severe drought stress. A cutting cannot correct underlying damage simply by being separated from the parent.
Gather cuttings in the morning while shoots are well hydrated. Use clean sharp secateurs and keep collected stems sheltered until you prepare them. The leaves are broad and can wilt quickly.
Take a softwood cutting at the right time
The RHS recommends softwood hydrangea cuttings from late spring to midsummer, with many softwood cuttings taken in April to June when flexible new growth is available.
Select a healthy non-flowering shoot tip around 8–10cm long, with several leaf nodes. Cut it cleanly from the parent just above a bud, then make the final base cut immediately below a node.
If you are taking several cuttings, keep them labelled and shaded. A pile of leaves left on a hot greenhouse shelf can lose much of its moisture before the first cutting reaches the pot.
Prepare the leaves to reduce moisture loss
Remove the lower leaves that would be buried in compost. Keep one or two suitable pairs near the top.
Hydrangeas have large leaves, which can lose water quickly. For particularly big leaves, some gardeners trim away part of each leaf blade, reducing the surface area while retaining enough foliage for the cutting.
Use clean scissors and avoid damaging the buds at the nodes. A sound stem with a few healthy leaves is more useful than a long leafy shoot that collapses through water loss.
Prepare the potting medium
Fill small pots or a propagation tray with suitable peat-free seed and cutting compost, with added drainage material if the mix requires it.
Moisten the compost evenly and let excess water escape. Soggy, airless compost increases the chance that delicate cutting bases will rot.
Make a hole with a dibber for each cutting. That prevents you from scraping the freshly prepared stem as you insert it.
Insert and label the cuttings
Push the lower bare section into the compost so at least one suitable node sits in the rooting zone. Firm the medium lightly around the stem.
Leave the retained upper leaves above the compost and space cuttings so foliage has room. Label with the hydrangea cultivar, source plant and date.
There is little benefit in putting twenty cuttings into one cramped pot. Crowding raises humidity around leaves without providing the airflow needed to keep them healthy.
Keep humidity up without creating a swamp
A propagator or a loosely supported clear bag can reduce moisture loss while the cutting lacks roots. Keep the cover from touching the leaves and ventilate regularly.
Place the pot in bright indirect light, not in fierce sunshine under clear plastic. A sealed propagator in direct summer sun can overheat quickly.
Check the compost and maintain gentle moisture. Don't pour water into a tray that is already saturated. The leaves need humidity, but the developing roots need oxygen in the medium too.
Know when new roots have formed
Rooting speed depends on temperature, cutting condition and cultivar. Watch for healthy new growth and a cutting that begins to hold firmly in the medium.
Wait until the roots form a useful little system before potting on. Do not tug at the stems repeatedly: early roots are fragile and easy to break.
If a cutting collapses, remove it and inspect the medium. Black mushy tissue often suggests rot, while dry crisping foliage can indicate excessive sun, low humidity or delayed preparation.
Move rooted plants to their own pots
Prepare small containers with a suitable peat-free potting compost. Lift each rooted cutting carefully with as much of its surrounding medium as practical.
Plant at an appropriate depth, firm lightly and water in. Keep newly moved plants in bright sheltered conditions while they recover.
Do not place a tiny rooted hydrangea into a massive pot. Excess compost can remain wet longer than the young roots can use it. Pot up in stages as growth increases.
Overwinter the young hydrangeas
Cuttings started early enough in summer may establish before winter, but they are still small plants and benefit from protection from severe frost and waterlogging.
Use a suitable cold frame or sheltered outdoor growing area, depending on the hardiness of the cultivar and local conditions. Don't keep them in a dark heated room if they require a normal seasonal rest.
Check moisture occasionally. Compost that remains saturated through freezing weather can damage roots; a pot that dries to dust for months is not ideal either.
Plant out when they're strong enough
In spring or autumn, established young hydrangeas can be planted into moist but well-drained soil, with enough light for their variety.
Many shrubby hydrangeas enjoy light shade and protection from severe afternoon heat. Some grow larger than expected, so check the mature width before planting next to a doorway or footpath.
Keep new plants watered through their first dry spells. A mature hydrangea may tolerate the garden's ordinary conditions, but a young propagated shrub has a small root system.
Why cuttings fail or refuse to flower
A flowering stem, overly long cutting or dry preparation conditions can reduce rooting success. Use fresh non-flowering growth and prepare it promptly.
Cuttings that root but do not bloom immediately are not necessarily failures. They may need several seasons to mature. A young hydrangea concentrating on leaves and roots is behaving normally.
If a plant grows leaves yet never flowers later on, look at species-specific pruning, frost damage and shade. Propagation and flowering are separate stages requiring different care.