From my perspective as an oleander, timing your pruning is crucial because it must align with my internal energy cycle. I flower on new growth. This means the branches that emerge in the spring and summer are the ones that will bear the beautiful blooms you admire. Therefore, the ideal time for a major shaping prune is in the late winter or early spring, just as I sense the days lengthening and the soil beginning to warm. At this time, I am still in a state of dormancy or very low activity. A significant cutback then allows me to direct all my stored energy from my roots into producing a vigorous flush of new, flower-bearing stems once the growing season truly begins. Pruning me at this time minimizes stress and maximizes my flowering potential.
Target late winter, after the worst of the frost has passed but before I put on a significant amount of new spring growth. In many climates, this is around February or March. The goal here is to shape my structure and encourage dense, bushy growth. You can be quite bold, cutting back leggy stems by one-third to one-half of their length. Make your cuts just above a leaf node or a set of leaves, angling the cut away from the node. This signals to me to send out new shoots from that point, creating a fuller, more compact shape. Avoid pruning too late in the fall, as the tender new growth I might produce could be damaged by winter cold, weakening me.
While the spring prune sets the stage, you can encourage even more blooms throughout my long flowering season with light summer pruning. As my individual flower clusters begin to fade and wither, it is helpful to deadhead them. From my viewpoint, a spent flower cluster is starting to divert energy into seed production. By snipping off the old flower cluster just below the base of the flower head and above the first set of healthy leaves, you signal to me that my work is not done. This gentle prompting encourages me to put energy into producing a new lateral shoot that will often bear another round of blossoms, prolonging the display well into the season.
How you cut is as important as when you cut. Please always use sharp, clean pruning shears. A clean cut heals quickly, reducing the risk of me developing diseases through a ragged wound. My sap is toxic and can cause skin irritation, so wearing gloves is as much for your protection as it is for mine. When you make a cut, do so at a 45-degree angle about a quarter-inch above a leaf node that faces the direction you want the new growth to travel—typically outward to maintain an open, healthy structure. This angled cut allows water to run off the wound, preventing rot. Remove any dead, damaged, or diseased branches whenever you see them, as they drain my resources and can be an entry point for pests.
If I have become overgrown, woody, or sparse, I may benefit from a more drastic rejuvenation prune. This is best done in late winter. You can cut me back much more severely, even to within 12 to 18 inches of the ground. This may seem extreme, but from my roots, it is a signal to regenerate completely. I will respond by sending up strong, new, healthy stems from the base. While I may not flower much in the first season after such a hard prune, it will restore a more youthful, vigorous form, leading to abundant flowers in the years to follow. This process revitalizes me, clearing out old, unproductive wood and making space for new life.
