Greetings, human cultivator. I am a Grevillea 'Robyn Gordon', a vibrant and resilient being. To help me thrive and shower you with my spectacular, spider-like crimson flowers throughout the year, you must understand my fundamental need: the light of my ancestral home. Here is my detailed perspective on the ideal light conditions for my existence.
My very essence is forged under the brilliant, unfiltered Australian sun. My genetic code is a map to open landscapes where the sun's energy is abundant and direct. For me, "full sun" is not merely a preference; it is a physiological imperative. This means I require a minimum of six to eight hours of direct sunlight each day. In this intensity, my photosynthetic processes operate at peak efficiency. My leaves produce ample sugars, fueling robust growth, strengthening my stems, and most importantly, generating the immense energy required for my near-continuous blooming cycle. Without this direct light, my internal systems slow, and I cannot express my true, floriferous nature.
The light I desire is strong and direct. Morning sun is particularly beneficial, as it gently dries the dew from my foliage, reducing the risk of fungal diseases, while the intense afternoon sun fuels the highest rates of photosynthesis. While I am adaptable and can tolerate very light dappled shade for a short part of the day, especially in regions with scorching afternoon heat, any significant shade is detrimental. Deep or prolonged shade forces me to become "leggy," as I stretch weakly towards the light source. My form becomes sparse, my growth soft and susceptible, and my flowering will be drastically reduced or cease altogether. My iconic foliage may also lose its dense, vigorous character.
Placing me in a low-light environment is a sentence of poor health. You will observe clear signs of my distress. The most obvious will be a significant reduction or complete absence of my vibrant flowers. Blooming is my most energy-intensive task, and without sufficient solar fuel, I must conserve resources for basic survival. Furthermore, my overall growth will be stunted and etiolated—spindly with large gaps between leaves. I will become vulnerable to pests like aphids and scale, and my weakened state will make me more susceptible to root rot and other pathogens, as my immune system is compromised without adequate energy.
I am robust and can handle intense heat, but I understand that in some climates, the sun's intensity can be extreme. In desert-like regions or areas with exceptionally hot, dry summers, the combination of all-day full sun and radical temperature swings can sometimes cause slight leaf scorch. In these specific cases, the ideal placement provides me with full sun for the majority of the day but offers a respite of very light, filtered shade during the absolute peak of the afternoon heat. This is a minor adjustment, not a fundamental change. Crucially, if you acquire me from a nursery where I was grown under shade cloth, I must be gradually acclimated to full, direct sun over a week or two to prevent sunscald on my tender, shade-grown leaves.
