Growing Oleander: The Complete Guide

When to Plant Oleander

Oleanders are only suitable for planting outdoors in frost-free areas. But planting in spring or fall is still the best practice. Plant anytime in spring when the weather and soil have warmed but before the heat of summer. In fall, plant once daytime highs have dropped, and you’re thinking about needing a flannel shirt before going outside. 

Where to Plant Oleanders

Oleanders grow most rapidly in full sun but will also do well in partial sun. They are quite heat-tolerant and can grow in poor soil as long as drainage is good. While they prefer alkaline soil pH, they’re a tough plant and will do well in most places. 

Remember that the oleander you bought in a pot at the nursery is going to get larger. Their size makes them well-suited for screening or privacy but less so for small spaces and tight locations. Dwarf oleanders do well in large urns and pots which can be brought indoors to shelter over winter.

How to Plant Oleanders

Oleanders are usually purchased from garden centers in one to three-gallon containers. They’re easy to plant and easy to care for, and you’ll be done in a few minutes.

• Remove all sod, mulch, and weeds from an area twice as large as the hole you will make. 
• Dig a bowl-shaped hole a little deeper than the root ball and two to three times as wide.  Loosen the soil on the sides and bottom of the hole–compacted soil makes it difficult for roots to penetrate and can cause poor drainage.
• Remove the oleander from its container. Prune any circling or girdling roots. Score the root ball to stimulate new growth if the shrub is rootbound.
• Test fit the oleander in the hole, checking the depth. The top of the root ball should rest at ground level. Enlarge the hole if necessary, or fill it in a bit for the proper fit. 
•  Backfill the hole using the native soil you removed, keeping the shrub vertical. 
• When the hole is halfway refilled, tamp the soil lightly but firmly around the roots to remove air pockets–don’t smash it. Give it a good drink of water, then keep filling the soil around the roots and firming it with your hands, watering again when complete.
• Apply mulch around the shrub, about 3-4 inches thick. Spread it evenly in a circle extending over the area you cleared and at least two feet from the base. Don’t let the mulch touch the trunk. The final mulch job should look like a flat disk, not a volcano.