Pelargoniums are easily propagated from cuttings in spring and autumn. The great thing about growing from cuttings is that you can keep the type true to the parent plant and with new young plants, you can be guaranteed of a fresh profusion of flowers. Early spring and later summer are the best times, but any time in spring, summer and early autumn will result in healthy cuttings. Early cuttings will flower that summer, while later cuttings will provide larger plants ready to flower the following summer.
Choose a healthy plant. Select shoots that look healthy and are not flowering. (It is possible to use flowering shoots if you have no choice but it’s best to avoid them.)
- Using a clean scalpel or sharp knife (secateurs can crush the shoots), cut off the shoot at a length of about 3-4 inches or 7.5-10cm.
- Trim the cutting to just below the node. Remove the lower leaves and scales at the base of the leaf stalks. Leave at least two leaves at the top.
- based seed compost. If you can’t find these, make a mixture of equal parts of peat and sharp sand. Use a container about 7.5cm/3 inches for individual cuttings, or a 12.5cm (5 inch) for up to five cuttings.
- Make holes in the potting mix using a dibble, finger or pencil.
- Insert the cuttings with care.
- Water the cutting to make sure that the compost is moist. The watering should be very light and avoid covering the cuttings with water, to avoid the growth of botrytis.
- The cuttings need a warm place for rooting. Preferably use a heating mat or propagator but a warm, sunny windowsill will do the trick, provided they’re shaded from direct sunlight (choose the side of the house without direct sun hitting it), or a shaded window. If the cuttings have bottom heat, cold air won’t be such an issue for them.
- Water lightly as the roots develop – on the whole, keep the compost dryish.
- You may see roots appearing within three days for some varieties, longer for others and longer if the air is cool. New top growth will appear once the roots form and if you tug the cutting gently, it will stay in place (thanks to its new roots).
- If you planted several cuttings to a pot, transfer to individual containers once they have developed roots.
- Rooting should start between a week to a month after taking the cuttings.
This video shows how to root geranium cuttings in water, a fast and reliable method of geranium propagation without any rotting of the stem cuttings.
Harden your plants off before planting them outside. Start the process 10 days to 2 weeks before planting, and begin by moving them outdoors to a shady spot (a cold frame works well for this purpose) for short periods. Gradually leave them outside for longer periods, and move them into brighter sunlight. Reduce your watering frequency to slow growth, but don’t allow the plants to wilt. Once they can endure the outside conditions without wilting, they are ready for planting.