How to Grow and Care for Oleander

Oleander (Nerium oleander) grows naturally as a mounded, round shrub, or it can be trained as a small single- or multi-trunked tree. The evergreen foliage of the oleander plant is dense, leathery, and dark green, offering a privacy screen when planted in groups or borders.

Delicately shaped, showy, fragrant flowers tend to be pink, while some varieties produce red, orange, yellow, or white flowers. Blooming for an especially long period, the 1- to 3-inch flowers appear from spring to summer and sometimes early fall and year-round in warmer climates.

Oleander is highly toxic to people and pets.

Warning

All parts of the oleander plant are toxic to humans and pets. This includes the smoke created from burning plant parts. Do not plant oleander flowers around areas where children and pets may play. Wear protective clothing and gloves when planting, pinching, pruning, or propagating oleander.

Planting Oleander

Plant oleander in cooler weather, such as in the spring or fall. Always wear protective clothing and gloves when planting oleander to avoid direct contact.

If planting in the ground, dig a hole at least twice as wide and deep as the root ball. Add compost to loosen the soil. Loosen roots in the ball, and put the plant into the ground so the root ball's top is flush with the ground. Place dirt back into the hole, and gently step on the soil to remove air pockets.

Give each plant adequate space, from 4 to 12 feet between plants. To grow oleander in containers, use large pots between 14 and 24 inches and make sure the containers have drainage holes.

Oleander Care

When shopping for an oleander bush, choose a plant that is one or two years old with a strong, straight, central stem. They are fast-growing, with a thick multi-stem, making them perfect for a living screen or hedge.

An oleander plant can become a tree or a bush. It can be allowed to grow in its natural bushy mound form or trained into a multi-stemmed or single-stemmed oleander tree at a height of 19 feet.

To create a single-stemmed tree, cut off all other stems and any side branches on the main stem to about half their length. Support the plant with a bamboo stake. Push the stake into the ground next to the stem and use plant ties to secure the stem to the stake.

Light

Oleander prefers full sun. It will also tolerate partial shade, but its foliage won't be as dense. It is also tolerant of heat, drought, wind, and coastal conditions.

Soil

Plant in well-drained soil for best results. Oleander shrubs can adapt to many kinds of soil conditions: poor soil, sandy soil, and a range of soil pH levels.

Like many native Mediterranean plants, oleanders prefer alkaline soil, but they will grow in acidic or neutral soil, adapting to pH levels between 5.0 and 8.3. Before planting, test the pH level of the soil. If the soil is overly acidic, mix in ground limestone, oyster shells, or wood ash.

Water

Water whenever the top inch of the soil becomes dry. If transplanting a container-grown oleander from one pot to another, choose a larger container with drainage holes to prevent the plant from becoming root-bound.

Fertilizer

Feed poor soil with a light dose of a balanced fertilizer during the plant's first spring and a light fertilization yearly thereafter. Moving forward, established oleander is not a heavy feeder.

Temperature and Humidity

Oleander can tolerate light frost and temperatures as low as 20 degrees Fahrenheit. In climates where temperatures reach any lower than that, grow the plant in a container and bring it indoors for winter, keeping it away from contact with people or pets.

Types of Oleander

Among many cultivars, consider the following:

• 'Calypso' is very hardy and has single, cherry red flowers.
• 'Isle of Capri' has single, light yellow flowers.
• 'Sister Agnes' has large single white flowers and is often sold as 'White Oleander.'
• 'Compte Barthelemy' has double deep raspberry flowers.
• 'Mrs. Roeding' has double pink flowers.
• 'Hawaii' has single salmon-pink flowers with yellow throats.
• 'Petite Pink' and 'Petite Salmon' are dwarf varieties that grow 3 to 4 feet tall.
• 'Variegata' and 'Variegatum Plenum' have variegated foliage.
  

How to Use Oleander in Landscaping

Oleander can be used in a variety of ways in the landscape. Consider the following:

• Larger varieties can be used as hedging and screening for boundaries, privacy, and obstructing views.
• Any size can be used on slopes and hills to mitigate erosion.
• Call attention to the plant by planting it as trees in a line along your driveway or flanking them on the sides of an entry or opening.
• Use potted oleander to hide unsightly parts of your home, such as outdoor HVAC units, tanks, or trash bins.

Propagating

Oleander can be propagated by stem cuttings. When propagating oleander, you must wear protective clothing and gloves when handling the plant.

Here's how to propagate by cuttings.

1. Remove all the leaves except the top two from the stem cutting.
2. If using rooting hormone, dip the cut end into the hormone.
3. Plant the cut end into the soil, at least three inches deep.
4. Cover the cutting with a plastic bag. Use a chopstick or pencil as a stand to prop up the bag, so it does not rest against the cutting.
5. Put the plant in a warm spot that receives filtered light.
6. Check for rooting by tugging gently on the cutting. If you get resistance, roots are forming. Remove the bag. The plant should develop roots within four to six weeks.

Pruning

Remember to wear protective clothing and gloves when handling this plant. The best time to prune oleanders is during late winter, just before new growth occurs (February through March). Oleanders bloom in summer on new growth.

Pinch the tips of young stems to prevent them from becoming leggy and also to encourage branching. Prune out any damaged or diseased limbs.

Tip

Deadheading, or the process of removing spent blooms, will stimulate oleander to produce even more blooms. To keep your oleander flowering for as long as possible, keep an eye on spent blooms and remove them with clean pruners.

Overwintering

Before winter weather arrives, cut the bush back generously by about two-thirds. If the plant is established in the ground, gingerly dig around the roots to lift the plant out of the ground. Pot the plant in good potting soil.

Care for oleander in pots by bringing the containers indoors. Place the pots in an area that is sheltered but still receives full sun, such as a porch or a garage with a window. Keep it out of reach of children or pets.

Common Pests and Plant Diseases

Oleander leaves contain latex, and extracts from the plant can make a strong insecticide. For this reason, plants are resistant to deer and rarely have severe issues with diseases or pests. They are especially resistant to verticillium wilt. Even so, keep an eye out for aphids, mealybugs, and scale.

The most damaging pests are oleander caterpillars. Mature caterpillars can move up the walls of adjacent buildings and reproduce near the eaves. Remove cocoons to manage the next generation, which could eat all the plant's foliage in a week or two.

From: thespruce