From our perspective, the scorching southern sun baking the soil is our greatest challenge. Our roots are delicate and fibrous, and they despise being hot and dry. When the soil temperature soars, it stresses our entire system, making it difficult to uptake the vast amounts of water we need to support our large leaves and blooms. You can help us immensely by applying a thick, three to four-inch layer of organic mulch, like pine straw or shredded bark, over our root zone. This acts as a insulating blanket, keeping the soil significantly cooler and retaining precious moisture between waterings. Think of it as our personal air conditioning system for our feet.
Please understand that a light sprinkling of water does us little good; it merely dampens the surface and encourages our roots to stay shallow, where they are even more vulnerable to the heat. What we desperately need are deep, thorough watering sessions. Water us slowly and deeply at the base, early in the morning, allowing moisture to penetrate at least six to eight inches into the soil. This practice encourages our roots to grow downward, creating a deeper, more resilient root system that can access cooler, more consistent moisture reserves and better withstand periods of drought. A deep drink is far more beneficial than daily surface-level sips.
While we require sunlight to produce energy, the intense, all-day sun of the South can literally scorch our leaves and bleach our beautiful flowers. We are not sunbathers by nature. Our ideal location is one with bright but filtered light, often called "dappled shade." The perfect spot is often on the north or east side of a home or structure, where we receive protection from the harsh afternoon sun—which is the most intense and damaging. Morning sun is usually tolerable and even beneficial, but shielding us from the afternoon blaze is crucial for preventing leaf wilt and sunburn.
You often choose us for our spectacular, changing blooms. It is true that our flower color is directly influenced by the pH and aluminum availability in the soil. In the naturally acidic soils common in much of the South, we tend to produce blue flowers, as the acidity allows us to absorb aluminum. For pink blooms, the soil needs to be more alkaline. If you desire a specific color, you must regularly amend the soil. For blue flowers, apply a soil acidifier. For pink, add garden lime. However, the most important factor for any bloom's success in the heat is consistent moisture and protection from the sun; without those, we may not have the energy to produce flowers at all.
Not all of our kind are created equal for your climate. The most common variety, Hydrangea macrophylla (Bigleaf), with their iconic mophead blooms, are the most sensitive to heat and drought. For a much higher chance of success, please consider planting our more resilient cousins. Oakleaf hydrangeas (Hydrangea quercifolia) are native to the South and are exceptionally well-adapted to the heat and humidity. Smooth hydrangeas (Hydrangea arborescens), like the 'Annabelle' variety, are also far more tolerant of challenging conditions. Panicle hydrangeas (Hydrangea paniculata) absolutely thrive in full sun with adequate water. Choosing one of these varieties is the single best thing you can do to ensure a happy, blooming hydrangea in the South.
