New growth on an orchid stem signals an active plant, potentially leading to new blooms or plants. This growth takes various forms, each indicating different developments for the orchid’s life cycle. Understanding these changes helps in providing appropriate care.
Identifying Different Types of New Growth
A flower spike emerges as a green, slender, somewhat flattened growth, often with a “mitten-shaped” tip. Spikes grow upwards, remain green, and appear from between the plant’s leaves.
A keiki, Hawaiian for “baby,” is a new plantlet growing directly from the mother plant’s stem, often from a node. It appears as a small bump, then develops tiny leaves and roots, forming a miniature version of the parent orchid.
Aerial roots have rounded, green tips and appear under the leaves. They are covered with velamen, a spongy tissue that appears silvery-white when dry and green when wet, helping the plant absorb moisture and nutrients from the air. Roots can grow in various directions, often downwards.
Environmental Factors for Healthy Growth
Creating an optimal environment is important for encouraging healthy new growth in orchids. Adequate light exposure is a significant factor; most orchids thrive in bright, indirect light. Placing them near an east or west-facing window is ideal, as direct sunlight can scorch their leaves. Consistent light levels help the plant regulate its growth cycles and energy production.
Humidity also plays a role in orchid health, as these plants naturally grow in humid tropical environments. A relative humidity level between 50% and 70% is beneficial for common orchid varieties. Maintaining this humidity, through a humidity tray or a room humidifier, supports new growth.
Temperature fluctuations influence growth, especially for flower spike initiation. Many orchids benefit from a slight drop in nighttime temperatures, about 7 to 10 degrees Celsius (13 to 18 degrees Fahrenheit) lower than daytime, to encourage flower spikes. Daytime temperatures between 18-29°C (65-85°F) are suitable for active growth.
Appropriate watering and fertilization practices underpin plant vigor. Orchids prefer to dry out slightly between waterings; overwatering can lead to root rot, while underwatering can cause dehydration. A balanced orchid-specific fertilizer provides necessary nutrients to fuel new growth. Healthy, plump roots and turgid leaves are indicators of a well-nourished plant.
Caring for New Keikis and Flower Spikes
Once new growth is identified, specific care adjustments help ensure its successful development. For flower spikes, support is necessary as they grow taller and heavier. A small stake carefully inserted into the potting medium, with the spike gently tied to it, prevent it from bending or breaking. This support allows the spike to develop upright, which is aesthetically pleasing and helps the plant manage the weight of future blooms.
As buds begin to form along the flower spike, it is important to maintain consistent environmental conditions, avoiding sudden changes in temperature or light that could cause bud blast. Patience is helpful during this period, as it can take several weeks for the buds to mature and open into flowers. After blooming, the spike can be trimmed back, either above a node to encourage secondary blooms or entirely if it dries and turns brown.
For keikis, patience is also key, as they need to develop sufficiently before separation. A keiki should have at least two to three leaves and roots that are at least 2-3 inches long before it is removed from the mother plant. Separating a keiki too early can prevent it from thriving independently due to insufficient resources. Once these conditions are met, use a sterile cutting tool to carefully remove the keiki, ensuring not to damage its roots or the mother plant.
After separation, pot the keiki in a small container, typically around 4 inches, using a fresh orchid-specific potting mix. Place the newly potted keiki in a location with bright, indirect light and maintain consistent humidity to help it establish. It can take up to three years for a newly potted keiki to mature and produce its first flowers.