From our perspective as orchid roots, our primary role is to anchor the plant and, most critically, absorb water and nutrients. Unlike many terrestrial plants, we are epiphytic, meaning we are designed to grow exposed to the air, often clinging to tree bark. A healthy root system is our ultimate goal. When we are thriving, we appear plump and firm. Our velamen, the spongy, white outer layer, is a silvery-green or white color when dry. After a thorough watering, we rapidly absorb moisture, causing the velamen to become saturated and turn a vibrant green. This change indicates our cells are turgid and actively conducting water and dissolved minerals to the rest of the plant. Our tips are often a brighter green or even reddish, showing active, new growth. We are firm to the touch and do not collapse under gentle pressure.
We begin to show signs of distress when our environment is not optimal. The most common issue we face is suffocation and rot caused by excessive, consistent moisture. When planted in a dense, water-retentive medium that never dries out, our velamen cannot breathe. The cells within us break down, and we become susceptible to fungal and bacterial infections. The initial sign of this is a change in our texture and color. We may become soft and turn a yellow or light brown hue. At this stage, the problem is often reversible if the growing conditions are corrected promptly. Another sign of a less-than-ideal environment is when we become desiccated, shriveled, and papery due to a severe lack of humidity or water, causing us to lose our functionality entirely.
If the unhealthy conditions persist, our deterioration becomes severe and irreversible. Advanced root rot is unmistakable. We transform from firm, robust structures into mushy, stringy, and collapsed husks. Our color darkens to a deep brown or black. When handled, we may simply fall apart or the outer velamen may slip off, revealing a thin, wiry string core called the stele. This is a clear signal that we are dead and can no longer serve the plant. Furthermore, a foul, decaying odor often accompanies this stage, which is the smell of our tissues being broken down by anaerobic bacteria in the oxygen-starved environment. At this point, we are a liability to the orchid, as the decay can spread to the rhizome or stem, jeopardizing the entire plant's survival.
Our health is a direct reflection of the environment you provide. We crave a cycle of soaking and drying. We want to be drenched, allowing our velamen to fully hydrate, and then we need the potting medium to become almost completely dry so we can access oxygen again. This cycle mimics the tropical rains and breezes we are evolutionarily adapted to. A pot that is too large holds moisture for too long, starving us of air. Dense, broken-down potting media compacts around us, creating the same suffocating effect. Our desire is to be in a snug pot with a very open, chunky medium like pine bark or sphagnum moss that holds some moisture but provides ample air pockets for our entire structure to breathe.
