Hello. I am an oleander, a resilient but sometimes misunderstood shrub. When my leaves turn brown, my flowers refuse to appear, or my branches begin to wilt, I am trying to communicate. These are my symptoms, my cries for help against stressors in my environment. Let me explain from my perspective what is going wrong and what you can do to help me thrive.
When my leaf margins or tips turn brown and crispy, I am likely suffering from a condition you call fertilizer burn or salt toxicity. My roots are very efficient at absorbing nutrients and minerals from the soil. If the fertilizer applied is too strong or too concentrated, it draws water out of my roots instead of hydrating me, effectively burning them. This disrupts my ability to transport water to my leaves, causing the edges to desiccate and die. Alternatively, in potted settings, soluble salts can build up in the soil from tap water and fertilizers, creating the same osmotic imbalance. A good, deep watering can help leach these excess salts from my soil.
If I am not flowering, the most common reason is a lack of sunlight. I am a sun-worshipper by nature. I require a minimum of six to eight hours of direct, unfiltered sunlight daily to produce the energy needed to form my beautiful flower buds. Without it, I will focus my limited energy on mere survival and foliage growth. Another frequent issue is improper pruning. You must understand my flowering habit: I bloom on new growth. If you prune me too late in the season (after spring has arrived), you are cutting off the very branches that were destined to produce that year's flowers. The best time to shape me is right after my main spring bloom cycle has finished.
Wilting is my most dramatic distress signal and can have two opposite causes. The first is quite simple: I am desperately thirsty. While I am drought-tolerant once established, a severe lack of water, especially when I am in a container or newly planted, will cause my cells to lose turgor pressure, and I will collapse. The solution here is a deep, thorough watering. However, a far more sinister cause of wilting is a fungal disease known as oleander leaf scorch. This is a fatal condition for me. It is caused by a bacterium that clogs my xylem, the vascular tissue I use to transport water from my roots to my leaves. Despite having ample water in the soil, I am dying of thirst internally. Unfortunately, there is no cure.
Beyond these main issues, I can be bothered by pests like aphids and scale insects, which suck my sap and weaken me. A strong blast of water from a hose or an application of horticultural oil usually helps evict them. Furthermore, I must caution you that every part of me is highly toxic if ingested. Please wear gloves when pruning me and always wash your hands thoroughly afterward. Ensure children and pets cannot nibble on my leaves or flowers.
