Ric Rac Cactus or Fishbone Cactus: Species Clarification and Care Differences

Ric Rac Cactus (scientific name: Selenicereus anthonyanus) and Fishbone Cactus (scientific name: Disocactus anguliger) are often mistaken for "twin brothers" due to their unique and similar zigzag or fishbone-shaped flattened stems. Although both belong to the Cactaceae family and originate from the tropical rainforests of Central America, they are classified into different botanical families. This means there are subtle but crucial differences in their morphology and optimal care requirements.

Species Revealed: Morphology and Classification

To differentiate between these two plants, the key is to observe their stem segments and flower characteristics.

Ric Rac Cactus (Fishbone Orchid Cactus / Zigzag Cactus)

Scientific name: Selenicereus anthonyanus, belonging to the Selenicereus genus.

• Stem Segment Characteristics: Its stem lobes are usually deeper and more "wild," with wavy edges resembling a fish's spine. The stem color is often dark green, and the texture is smooth.

• Flower Characteristics: Ric Rac Cactus flowers are "night owls," typically opening at night. The flowers are white or cream-colored, emitting a charming fragrance, with slender petals that emerge quietly from the indentations of the stem segments. Although the flowering period is short, the sight of them blooming at night is extremely beautiful.

• Growth Habit: This plant typically prefers to trail or creep, making it ideal for hanging baskets, where its stems can grow quite long.

Fishbone Cactus (Fishbone Cactus / Zigzag Cactus)

Scientific name: Disocactus anguliger, belonging to the Disocactus genus.

• Stem Segment Characteristics: Compared to Ric Rac, Fishbone Cactus stem lobes appear more "regular," with shallower incisions and neat "serrated" edges, like a slender fishbone, but with smaller, more uniform "spines." The stem color may be lighter, slightly yellowish-green, and the surface sometimes has fine textures.

• Flower Characteristics: Fishbone Cactus flowers also mostly open in the evening or at night, usually pale yellow or white, with a fresh fragrance. Their flower shape may be slightly fuller than Ric Rac Cactus, and the petals are relatively wider.

• Growth Habit: It also prefers to trail or creep, but the texture of the stems and the pattern of the lobes are key to distinguishing these two plants.

From a botanical classification perspective, although both genera belong to "cacti," there are significant differences in their evolutionary paths and genetic characteristics. The Selenicereus genus typically includes species with longer, distinctly angled stems and large, nocturnal flowers (for example, the commonly consumed dragon fruit also belongs to this family). The Disocactus genus, on the other hand, consists more of flattened-stemmed, richly colored, and mostly epiphytic cacti.

Care Differences: Their "Little Quirks"

Although both are epiphytic cacti in tropical rainforests, growing on trees, and their basic environmental requirements are similar, we still need to focus on specific aspects during cultivation due to subtle species differences and native climate conditions.

1. Light

   • Commonality: Both prefer bright, indirect sunlight, especially avoiding strong midday sun. In their native rainforest environment, they usually hide under tree canopies, enjoying dappled, filtered light.

   • Subtle Differences: Ric Rac Cactus may be more tolerant of slightly shadier environments, while Fishbone Cactus will have prettier stem colors and more abundant blooms if it receives sufficient but filtered sunlight. It is crucial to avoid insufficient light, otherwise, the stems will become thin and leggy, and the color will appear pale.

2. Watering

   • Commonality: Both like moist soil, but absolutely no standing water in the pot. The rule of thumb is to water thoroughly when the soil surface feels dry, ensuring no water accumulates at the bottom of the pot.

   • Subtle Differences: During the growing season (spring and summer), Ric Rac Cactus may require more frequent watering, as it might inhabit a more humid environment in its native habitat. Fishbone Cactus also needs to be kept moist, but during the winter dormancy period, both need significantly reduced watering frequency, allowing the soil to dry out appropriately. When judging watering time, you can usually assess by the weight of the pot or by inserting your finger two to three centimeters into the soil, watering when it feels dry.

3. Humidity

   • Commonality: As "natives" of tropical rainforests, both thrive in high-humidity environments.

   • Subtle Differences: Ric Rac Cactus may have a stronger preference for higher air humidity. If your home environment is dry, you can regularly mist around the plant (being careful to avoid water droplets staying on the stems for too long to prevent fungal infections), or place a humidifier or water tray to increase humidity. Fishbone Cactus also likes high humidity, but under good ventilation, its humidity requirements may be slightly lower than Ric Rac Cactus.

4. Soil

   • Commonality: Both require well-draining, organic-rich soil.

   • Subtle Differences: As epiphytic plants, both have extremely high demands for soil aeration. It is recommended to use specialized cactus and succulent soil mixed with orchid bark, perlite, and coco coir to simulate their native growth state in tree crevices and humus. Ric Rac Cactus may be slightly more adaptable to slightly acidic soil, while Fishbone Cactus has roughly the same pH requirements. The key is to ensure good drainage and aeration of the soil.

5. Temperature

   • Commonality: Their most comfortable growing temperature ranges between 18°C-28°C. Both are very sensitive to cold, and winter temperatures must not fall below 10°C, otherwise, they are susceptible to frost damage.

   • Subtle Differences: The temperature requirements for these two plants are largely consistent; both need to avoid drastic temperature fluctuations.

6. Fertilization

   • Commonality: During the growing season (spring and summer), apply a diluted liquid fertilizer every 2-4 weeks.

   • Subtle Differences: A balanced fertilizer can be used, or one with a slightly higher phosphorus and potassium content to better promote flowering. Ric Rac Cactus may have a slightly higher demand for phosphorus fertilizer just before flowering. Fertilization should be stopped during the winter dormancy period.

7. Pests and Diseases

   • Commonality: They primarily face threats from common pests such as mealybugs, aphids, and spider mites. Overwatering can also easily lead to root rot or stem rot.

   • Subtle Differences: Their resistance to pests and diseases is roughly the same, so maintaining good ventilation and appropriate humidity is key to preventing these problems.

Summary

Ric Rac Cactus (Selenicereus anthonyanus) and Fishbone Cactus (Disocactus anguliger) are fascinating plants that are easily confused morphologically. However, careful observation of the stem lobe shape (Ric Rac is deeper and more irregular; Fishbone is shallower and more regular) and flower characteristics can clearly differentiate them. In terms of care, as tropical epiphytic cacti, they share common needs for filtered light, high humidity, well-draining soil, and a warm environment. The subtle care differences mainly lie in their preferences for light and humidity, with Ric Rac Cactus possibly preferring a slightly shadier and more humid environment. Understanding these "little secrets" between the species will help enthusiasts better care for them, allowing these unique "fishbone" cacti to bloom with their distinct beauty in your home!