Greetings from the Bougainvillea! To truly thrive and produce the vibrant, papery bracts you adore, my needs are quite specific. While I am known for my toughness, the right foundation of soil and nutrition is not a mere preference; it is a requirement for my spectacular display. Here is what I, the plant, need from you.
My greatest fear is wet feet. My roots are highly susceptible to rot if left sitting in soggy, waterlogged soil. Therefore, the single most important characteristic of my growing medium is excellent drainage. A dense, moisture-retentive soil like standard garden clay is a death sentence for me. I crave a loose, airy mix that allows water to flow through freely. An ideal potting mix for me would be a cactus or citrus blend, or a homemade medium of two parts peat moss or coco coir, one part compost, and one part coarse perlite or pumice. This combination provides moisture retention without sogginess, aeration for my roots, and a slight organic component to kickstart my growth.
My ability to access the nutrients you provide is governed by the soil's pH level. I perform best in a range of slightly acidic to neutral (pH 5.5 to 7.0). In this range, essential minerals like iron, manganese, and phosphorus remain soluble and available for my root system to absorb. If the pH becomes too alkaline (above 7.0), I will likely develop iron chlorosis, where my newer leaves turn yellow while the veins remain green, stunting my growth and bract production. You can occasionally amend the soil with a small amount of sulfur to lower the pH if necessary.
I am a heavy bloomer, not a heavy feeder of nitrogen. While nitrogen is crucial for healthy green growth, too much of it will cause me to direct all my energy into producing vast amounts of foliage at the expense of my beautiful bracts. You will get a lush, green bush with very few flowers. What I truly need is a fertilizer that is high in phosphorus (the middle number in the N-P-K ratio), which directly promotes blooming. A fertilizer with a ratio like 6-8-10, 10-20-10, or similar is perfect for me. Look for labels that say "Blossom Booster" or "Bloom Formula."
During my active growing season (spring through early fall), I appreciate regular feeding. However, I am sensitive to salt buildup from fertilizers, which can burn my roots. It is far better to feed me with a weaker, diluted solution more frequently than a full-strength dose monthly. A good rule is to fertilize me every two to three weeks with a water-soluble, high-phosphorus fertilizer mixed at half the recommended strength. Please cease feeding me in the late fall and winter when I am dormant; I am not growing and cannot use the nutrients, which will only accumulate and harm me.
