Rhododendrons fascinate in the spring with flowers in all imaginable colors. Two-tones in particular are becoming increasingly popular and are very much in vogue. If you miss such a magnificent specimen in your garden, you can either buy it or multiply it yourself.
Rhododendrons arouse the passion for collecting in many hobby gardeners. Because the joy of successfully creating two or more plants from one is fun. Most rhododendron varieties can be propagated by grafting them. Propagation by cuttings is only recommended for certain rhododendron varieties.
The 7 most common propagation practices at a glance:
- sowing
- offshoot
- moss
- lowering
- Graft
- cuttings
- refine
Propagation by sowing - a long game of patience
Germinable seed capsules are significantly more voluminous than unfertilized ones. The fresher the seed, the easier it is to germinate and to propagate. Embedded in a peat substrate with sand and perlite (€37.51), the seed will germinate in a greenhouse after 4-6 weeks, depending on the rhododendron species.
But only after a year are you spoiled for choice. Then you can prick out the delicate green and accelerate growth by carefully fertilizing. The first flower buds form after 2 years at the earliest. You'll have to wait patiently…
Propagating rhododendrons by cuttings
After flowering is the best time to cut offshoots. Older rhododendrons with side shoots close to the ground are best suited for this. Select a side shoot and use a sharp knife to cut the bark about 15 centimeters below the leaf whorl. Now put a match in the notch to keep it open. The incision forms wound tissue (callus). New roots will grow from it next spring. Now carefully separate the new plant from the mother plant without damaging the roots. Plant the newly acquired offshoot in a semi-shady place and water it vigorously.
Mossing, drooping or grafting ideal for clones
Just want to clone a duplicate of your rhododendron? This is achieved by removing moss, lowering or grafting. When removing the moss and lowering, you cut a young branch close to the ground at an angle and lower it into a peat bed. As soon as roots form, separate the shoot from the mother plant.
Abmoss differs by wrapping the cut surface with some damp spaghnum moss. Finally, a black plastic collar is tied to the branch at the top and bottom with a wire and kept warm and moist. Now it's time to wait and keep your green fingers crossed. Roots will sprout from the cut site after 1 to 2 months. Then cut off the branch and pot.
Grafting with rhododendron seedlings as a base
Grafting with rhododendron seedlings as a base requires some experience. Because species like the rhododendron variety Cunningham's White react differently to documents.
The stem diameter of scion and rootstock must be the same thickness. You slant both, press them together and wrap the grafting point with raffia. Put a plastic hood over the base, which is in a pot, and tie it tight to create a greenhouse. If the pot is in a bright, shady and cool place, the scion will grow within a year. The fact is: Not all wild species can be grafted or benefit from a more robust growing rootstock.
Propagation by cuttings or grafts
These are vegetative propagation methods with a plant that has the same characteristics as the mother plant. The ideal method if you want to propagate a new breed easily, quickly and inexpensively.
Basically, you only take the head cuttings from the end of the shoot. Break off existing flower buds. Cut the cuttings to a hand's width, remove the lower leaves and stick them in nutrient-poor potting soil.
And how does it continue? Overwinter rooted cuttings in the greenhouse and only pot or plant out next spring at planting time.
tips and tricks
Whether you are a hobby gardener or a professional - if you want to propagate rhododendrons, the following applies: experimenting is about studying. Because practice makes perfect and damage makes you smart. Therefore, I wish you a lot of patience and damage, but even more prudence!