Flower Focus: Oleander (Nerium)

Oleander plants, also known as Nerium oleander, are among the most adaptable of shrubs.

They boast a variety of uses in both coastal and southern landscapes and are classed as an extremely sturdy plant.

They’re able to withstand a number of difficult conditions, including problematic soil, high PH, salt spray, high heat, strict pruning and drought.

However, despite being tolerant to unruly surroundings, they’re unable to withstand colder temperatures. If you live in an area that brings cooler weather, don’t be put off though. Simply grow your oleander plant in a container and when the temperatures drop, take it indoors.

Oleander – all you need to know

One thing to be aware of when growing oleander is its poisonous traits, which can affect small children and pets.

Consuming even a small amount of the flowers, foliage or shoots can be lethal, and both the flowers and foliage can trigger a severe skin reaction. This doesn’t mean you should avoid growing this versatile shrub, it simply means you need to take more care when choosing where to plant it – always wear gloves and long sleeves when working with the oleander plant.

Oleander: Flowering times

Oleanders flower from spring up until the end of the summer months.

When in full bloom, they showcase oversized clusters of picture-perfect flowers, which sit at the tips of the stem, in hues of white, yellow, pink or red. They flower well when placed in full sunlight; whilst some species are also able to flower in partial shade. Although oleanders are considered hardy, they can sometimes be susceptible to frost. Despite this, the shrub generally recovers, even if it appears completely destroyed.

Oleander origins

Universally known as nerium or oleander, due to its seeming likeness to the unrelated olive Olea, this particular specie of plant is so widely cultivated, its exact region is unknown. Some believe it is native to southwest Asia.

oleander

Oleander varieties

Oleanders look a little like olive trees but with flowers. They can grow between three and 20 feet in height and offer a sweet scent and an assortment of different hued flowers. There are more than 50 types of oleander available for the garden, including ‘Mrs. Lucille Hutchings’, ‘Pink Beauty’ or ‘Hardy Pink.

All of these variants are relatively tall. If you prefer white to pink blossoms, opt for ‘Album’ cultivar, which can grow to 18 feet tall. Dwarf versions of Oleander Plants are also available and are perfect for smaller gardens, as they seldom grow over four feet in height.

Tips on how to grow oleander plants in containers

This Mediterranean plant has proven prevalent in Europe for many years. If you wish to grow this perennial plant in cooler climates, you must do so in a container. Growing oleanders in plant pots is easier than you think though. Once established, ensure you feed your plants with a high potassium fertiliser every two weeks to encourage your shrub to flower. This procedure should continue from spring until late summer.

When the temperature begins to fall, protect your oleander plants by moving your containers indoors. If your plant is a little on the large side, prune it back. Any cuttings you’ve taken should be saved, especially if you wish to propagate new plants. For best results, place plants in a basement or cool garage.

In the spring, when the freezing weather has passed, begin to move your plants outdoors. This should be a gradual process and oleanders should only be left outside for an hour on the first day, and then a further hour every day for a week after. Try to find an area that boasts partial sun to allow for a period of adjustment before moving your plant in to full sunlight.

Oleander seed propagation

After oleander has flowered, it’s able to produce seedpods. If you wish to grow oleander plants from seeds, simply gather and store these seedpods, being careful not to let them touch your skin as they can cause irritation. Over time, these seeds will dry and split open, showcasing an array of feathery, fluffy substances. Attached to these entities are tiny brown seeds.

When planting these seeds, it’s a good idea to pay attention to temperature. Oleanders are unable to withstand freezing temperatures, which is why many bring these plants inside during the cooler months. However, if you reside in an area that is resilient to frost, you can plant oleander seeds outdoors at any time.

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How to grow oleander from seeds

If you wish to plant oleander shrubs from scratch using seeds, begin by selecting a number of small pots or alternatively, a seed tray.

Fill with peat and moisten the top couple inches. Once prepared, gently press the seeds into the top of the peat without covering them. You’ll then need to cover the pots and containers with cling film, before positioning them in a warm, dry place. The perfect temperature is 20°C.

For best results, invest in some grow lights and spray the peat on a regular basis to avoid it drying out. Seeds can take anything from one month to three months to germinate. As soon as you see the seeds sprouting, remove the cling film. When you notice leaves on the seeds, only then should you think about transferring them to a larger pot or to the garden.

Oleander care

Oleander care is almost maintenance-free, which makes it a popular plant choice for those with little time on their hands.

You should reshape and prune any impaired parts of the shrub to inspire new growth. When in full bloom, they offer an incredible display of long-lasting flowers. Even though these plants are able to withstand drought, they tend to look their best during dry spells, which is when they’re entitled to plenty of water.

As with many plant species, it’s important to avoid saturating the soil, which means ensuring good drainage. If not, the plant risks becoming susceptible to root rot. One sign your plant is getting too much water is yellowing leaves.

What to do when your oleander won’t flower?

If your plant is struggling to bloom, there is likely a perfectly rational reason for this. For example – Is its light being blocked out by other shrubs? Is it getting enough water? Does it appear to have a disease? Or has it been watered too much? Thankfully, the majority of these ailments are easy to fix.

Fertiliser

If you only have poor soil to work with, you should feed the plant with a balanced fertiliser. This should be applied at the beginning of spring. Once your oleander plant is established, they no longer require regular fertilisation.

Pruning

To reduce length, especially if planting in a smaller area, simply pinch out the tips of young stems. Regular pruning is another way to encourage healthy growth, and removing broken or unwell leaves, branches and flowers is a must in late autumn.

Diseases

Although these plants require little care, there are still certain diseases you need to watch out for, many of which can hinder the oleander plant’s ability to bloom. Bacterial pathogens are usually behind the majority of oleander plant diseases.

They’re also susceptible to a number of fungal pathogens. These viruses can contaminate plants through pruning cuts, and are often transferred by insects that forage on the plant tissue. Other diseases comprise cultural disorders, which can be caused by inadequate water or nutrient shortages. Things to look out for include drooping, yellowing leaves, wilted stems and knotty growths.

Another common pest to attack the oleander is the aphid – a bright yellow, sap-sucking insect. Whilst these pests can cause severe harm to certain species of plant, when they attack the oleander, they’re more of an eyesore than something that is going to cause a detrimental effect.

So how do you get rid of unwanted aphids? The best way to remove them is to use cultural controls, as it’s the tender oleander shoots that attract these pests. If you reduce both irrigation and fertilisation, your oleander will produce less of these. If your plant suffers from heavily invested shoots, it may be wise to remove these altogether. Another option comprises washing the aphids off using a hose. You can also apply Neem oil to the affected area of the plant – a common garden tool celebrated for its anti-fungal and pesticide properties.

Treating Oleander Diseases

Whilst there are no treatments for bacterial and fungal diseases, there are a number of steps you can take to prevent these ailments from occurring.

Promote healthy plants by ensuring you plant them in full sunlight, apply quality fertiliser and give them adequate water in times of drought. Avoid using a sprinkler in your garden as plants that are constantly wet can provide a breeding ground for bacteria. Additionally, prune your plants regularly and remove diseased or dead stems. You may also wish to disinfect your pruning tools using a mixture of ten parts water and one part bleach.

Other uses for Oleander plants

If you wish to create a natural barrier in your garden, an oleander hedge may be just the ticket. Certain varieties of Oleander can grow to an impressive 20 feet tall. This plant’s thick, upright growth makes it an ideal option for a privacy wall or screening plant. They’re also extremely sturdy and can withstand drought, salt and pollution. When in bloom, your new organic wall, with its beautiful, perfumed clusters, will bring your garden to life.

Dwarf Varieties of Oleander Plants

If you only have a small garden to work with, dwarf varieties are a great option as they seldom reach more than four feet in height. Popular varieties include ‘Algiers’, ‘Petite Salmon’ and ‘Petite Pink’.

Petite Pink is a compact, evergreen version of the oleander and it features sets of funnel-shaped five petaled flowers when in bloom. As the name suggests, the flowers are a soft pink colour and this is a particular favourite in seaside areas as it capable of tolerating both winds and salt spray. It is however less cold hardy than other species and maybe better suited to more sheltered areas. Petite Salmon differs in that its flowers are a different hue, namely salmon pink.

Oleander – Resources

Author: Lily Calyx

Flower expert, gardening enthusiast and creative mind behind our blog.

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