Propagating oleanders by seeds and cuttings – instructions

Rose laurel, as oleander is often called, can be used in a variety of ways in the garden and in the conservatory. The heat-loving plant prefers a solitary position in a sunny location.

Native to Asia and the Mediterranean, the oleander can reach a height of up to five meters in the garden. However, due to its lush growth, the evergreen plant with the intensely fragrant flowers needs a lot of space and freedom. Oleander can be used in many ways on your own property, especially as a container plant. For example, you can line your terrace with the impressive plants or create an eye-catcher in your front yard.

In order for the plant to shine in all its glory, it needs a warm, wind-protected and sunny location. In order to transform your own garden into a Mediterranean landscape, oleander can also be optimally combined with other sun-loving plants. Cultivate the plants together with citrus plants, olive trees or palm trees, for example. So that the individual plants can still develop optimally, you should give them enough space and a certain minimum distance from each other.

Vegetative propagation

The Mediterranean plant is easy to grow from cuttings. The best time for this type of propagation is between June and September. Root formation can take place equally on older and younger shoots. However, you should preferably use young, unwoody branches. Nerium oleander is a poisonous beauty and the sap can also cause severe skin irritation. Therefore, always wear gloves when working with the plant and avoid contact with your mouth and eyes.

• Cut off several young shoots just below a leaf node
• Length of the cuttings between 15 and 25 centimeters
• completely remove the lower pairs of leaves
• Place the cuttings in a glass of water
• Keep the container bright and warm, avoid direct sunlight
• after about 4 weeks the first fine roots form
• Put the rooted cuttings in a container with a humus-rich substrate

You can root the cuttings directly in poor soil. For oleanders you need a deep flower pot with a small diameter. Again, the lower pairs of leaves must be completely removed to counteract potential rot formation. To speed up root formation, you can increase the humidity. If you don’t have a greenhouse available for this, you can wrap a clear plastic film completely around the flower pot and cutting. The film must be removed for a few hours a day to allow air circulation. Keep the substrate sufficiently moist, preferably you should only water with a water sprayer. Once new leaves and shoots form, the new roots have fully formed. Now is the best time

Another way of vegetative propagation is by dividing the roots. Oleander often has a bushy appearance with three or more strong main stems that shoot out. Divide the root system so that each piece of plant has one of these shoots. Then cultivate the pieces as usual. Start doing this between April and June, before the plant starts flowering. Because if oleander is massively disturbed during this time, the resistance of the dogbane plant to fungal pathogens and bacteria decreases.

Generative propagation

Older oleander plants are extremely floriferous, you can get seeds for propagation from the feathery, black fruit capsules. Unlike many native plants, oleander seeds do not need to be stratified. Sowing can be done all year round, but cultivating in February on the windowsill has proven to be ideal. Heat and high humidity also ensure that the plants germinate reliably. However, do not lose patience, because the cultivation of seeds is tedious and can take several weeks.

• Let the seeds soak in lukewarm water for about 6 hours beforehand.
• Use a shallow dish for sowing.
• Holes on the bottom of the container allow excess water to drain off more quickly.
• Preferably use lean cultivation substrate, such as coconut fibers.
• The location must be bright.
• Cover seeds lightly with soil.
• Keep evenly moist with a water spray.

Here, too, you can increase the humidity using a perforated, transparent film. Build a simple wooden frame, for example by sticking kebab skewers on the side of the container and carefully stretching the foil over it. In this way, the seedlings do not later come into direct contact with the condensation water. The wooden sticks often tend to mold in the moist environment of the floor. Remove these spots immediately.

It can take several weeks for the first shoot tips to appear. Water regularly, but avoid washing away the soil. The young oleander must be transplanted as soon as the seedlings have reached a size of about 8 centimeters. This is especially important when the plants are too close together. If you relocate Nerium oleander outdoors, the important tip also applies here: First, slowly accustom the plants to direct sunlight. It is usually sufficient if you protect the plant with a parasol in the midday hours.

Tips for proper care

There is a widespread misconception that oleanders are generally sensitive to cold temperatures. But you don’t necessarily have to relocate the tall plants to the cool winter quarters at the end of September. Because some of the well over 160 varieties are frost-resistant and can be cultivated outdoors all year round in areas with mild winters. Only a protective layer of bark mulch has to be applied to these plants. With young or newly planted plants, you should also wrap the upper part with a special fleece. Other Nerium oleander species need a frost-free, cool winter quarters by October at the latest. The temperature must not exceed 10°C in order to avoid pest infestation and germs.

cut

Oleander belongs to the type of plants, which can be regulated in height by regular pruning. In autumn you can shorten the growths by up to 2/3. Please note, however, that flowering occurs only on older shoots. If these are completely removed, there will be no flowering in the same year. Longer shoots that occur when pruning can be used as cuttings. In autumn, you should also remove the mature seeds and keep them in a dry place until sowing. If you do not want to propagate oleanders, you can also dispose of the plant parts directly at a green waste collection point. Decomposition takes a long time on your own compost. Clean and disinfect all equipment you used for gardening.

repot

Regular watering is even more important than cutting and repotting. Especially on hot summer days, oleander develops an almost insatiable thirst. Waterlogging does not matter, because even standing water in the saucer is quickly absorbed by the plant. So that the valuable moisture does not evaporate while you are watering, you should only do this in the early morning or late afternoon. Check regularly whether the substrate feels dry and water immediately if necessary. If the oleander is exposed to drought for a long period of time, the lower leaves turn yellow and the formation of flowers also suffers as a result. Even during hibernation, the plant needs to be watered moderately with lukewarm water.

As soon as the oleander plants propagated by seeds or cuttings have reached a certain size, they should be transferred to a stable container. However, oleander has high demands on the soil and the nutrients, which you should also offer potted plants. Mix conventional potting soil with clay and garden lime. It is fertilized with long-term or liquid fertilizer, which is dosed and administered directly via the irrigation water. The plant is dormant throughout the winter and its metabolism is kept to a minimum. During this time there must be no supply of nutrients.

frequently asked Questions

Fine webs can be seen on the cuttings grown in winter, what is the reason?
The cold season is unfavorable for growing cuttings and seeds. During the cold months, oleander takes a break from growing and the development of the roots is delayed enormously as a result. Fine webs, which are usually hardly recognizable at first glance, indicate spider mites. The small mites are only a few millimeters in size and feed on the cell sap of the host plants. A warm environment and dry room air promotes infestation with this type of pest. In addition to the spider web-like formations, a sticky plant surface is a clear indication of the animals. Take effective countermeasures immediately. Because with an increasing pest population, the plant also suffers more and more.

Can I scratch orchid seeds before sowing?
To make the seed more permeable to water and thus minimize the germination time, larger seeds can be scarified. Use a nail file or medium-grain sandpaper to slightly roughen the hard shell of the seeds. Then soak in warm water overnight and plant according to the instructions above. Heat and high humidity also play an important role for oleanders. If these conditions are not met, the germination of the plants is delayed. There is a high risk of injury if you try to scratch the surface of the seeds with a knife. Therefore, refrain from such an action.