The bushy, abundantly flowering oleander plant brings a Mediterranean flair to the terrace and garden. Proper care and regular pruning are definitely crucial for flower formation. We explain in detail how to prune the oleander in spring and autumn and what you need to take into account in order to promote rapid growth. We will also provide you with a sketch showing the various cut shapes. This is how you keep your exotic looking shrub in shape. And for inspiration we also show you some beautiful gardens where the oleander plays the main role.
Cutting oleanders: the right care
The oleander is an evergreen, white, pink, light yellow or red flowering perennial from the Mediterranean region. The shrub grows bushy, has three or four main shoots and can reach heights of up to 3 meters. A sunny location, regular watering with temperature-controlled tap water and a loamy substrate promote flower formation in the summer months. Since the plant is not hardy and can only tolerate light frost, it must be moved to a warmer location at the end of autumn. A greenhouse or winter garden is perfect for this purpose.
Here are the top grooming tips that are guaranteed to grow your oleander quickly.
The right location is the direct sun. If you have a container plant, you can put it on display in a sheltered spot on the terrace. During the flowering period from May to September, the shrub must also be protected from rain, as the flowers do not tolerate rainwater well and often rot.
An earth substrate with a high proportion of lime is ideal for the plant, which comes from southern Spain.
Young perennials grow very quickly and therefore need a lot of nutrients. In spring, from mid-March to the beginning of April, you can provide them with long-term fertilizers. Regular fertilization is also a must in the warm summer months when the plant is blooming. You can add liquid fertilizer to the water two to three times a month. Oleanders that you pruned back vigorously in spring (we explain in detail below when pruning is necessary) also need long-term fertilizers in spring. All other plants that are healthy and at least three years old only need to be fertilized with liquid fertilizer once a week in summer.
Wintering: As already mentioned, the Mediterranean plant is not hardy and must be overwintered in the months between November and March either in a light greenhouse / winter garden or in the garage in a dark place. The following rule of thumb applies: the temperature in the room should be between 2 and 5 degrees Celsius. The room should also be ventilated once a week.
Trimming oleanders: when is a pruning appropriate?
We have already addressed the most important points regarding maintenance, because the cut depends on it. Depending on whether the oleander is healthy or infested with scale insects, for example, whether the plant is young or several years old, and what its crown looks like, different cuts are possible. We give you an overview:
1. Young plants usually do not need pruning in autumn. However, you will need to regularly remove transverse branches from inside the shrub. Sick branches are also cut off. Before wintering, you can also cut any parts of the plant that have sprouted too long and that hang down over the edge of the pot. The plant therefore takes up significantly less space in the winter garden. Usually the experts advise you to give the plant a thorough check every three to four weeks and, if necessary, give it a very slight corrective cut.
2. Vigorous oleanders over 2 years require more care when it comes to cutting. In the case of a large plant, it makes sense to cut it back before wintering. This protects the shrub from scale insect infestation and promotes flower formation. Basically, the following applies: As soon as you notice that the new branches are growing straight through the interior of the bush and the plant is producing significantly fewer flowers than in the previous year, you need to cut it in autumn. You have to cut the shoots back to the first bud so that they can form new flowers in the next spring. Cut back up to 30% of all shoots.
3. A pruning in which the entire crown is severely pruned in spring (from mid-March to early April) is only possible in exceptional cases. If the plant has grown greatly in width or if it is attacked by pests, then all of its shoots are cut back by 20 cm from the ground. It can tolerate pruning very well, but it can no longer produce flowers in the same year.
Cutting oleander – instructions with picture
With the drawing above we try to illustrate the different types of cuts again. If you want to prune your oleander, then you should consider a regular pruning, a pruning in autumn or a complete pruning in spring.
Caution! The oleander is a poisonous plant, so be sure to wear gardening gloves.
With a caring pruning, only individual twigs and shoots are cut back to the first bud (see sketch, above, left).
When cutting in autumn, before wintering, a maximum of 30% of all shoots are cut back to the first bud. (see sketch, above, in the middle) This way the plant can produce flowers in the same year.
When pruning in spring, all branches are cut back 20 cm from the ground. The plant recovers, grows strongly in spring and summer, but does not produce new flowers until the next year. (see sketch, above, right).
If the oleander is healthy, but individual shoots are growing transversely (see sketch, in the middle, left), then it needs a cut in autumn. On the sketch below, on the left, the end result is shown – this is what a healthy, cut shrub should look like before wintering.
The different types of cuts are also marked on the sketch. A perennial in the garden is cut back every two years in the USA because it does not have to be overwintered. But when it comes to a container plant, it makes more sense to cut it more compactly. Some hobby gardeners cut them in the shape of a tree (high trunk), others love the shrub shape and leave several stems in the pot.
You can tie up newly planted oleanders in spring and summer to be on the safe side. You can anchor them with a tripod or with two vertical pillars.