Disocactus (Epiphyllum) ackermannii 'Red tip'

The horticultural background of Disocactus ‘Red Tip’

Disocactus ‘Red Tip’ belongs to the wider Disocactus ackermannii horticultural group rather than being identified as the wild species alone. Its exact species and hybrid parentage have not been established; the wider group combines Mexican Disocactus ancestry with related red-flowered forest-cactus hybrids.

Seasonal care for a dry-growing plant

Light

Give Disocactus ‘Red tip’ strong filtered daylight and a controlled amount of gentle direct sun, ideally close to an east window. Hot midday or west sun can turn the entire surface yellow-red, bleach it or cause corky burns.

Watering

During active extension, water after the upper third of the medium dries and before the root ball is dry throughout. Permanent moisture causes root loss regardless of stem colour.

Temperature

Maintain steady indoor warmth during growth. Once buds form, keep the position and temperature stable.

Humidity and airflow

Average household humidity is generally adequate. Let water leave the segment joints after cleaning.

Fertilising

Use a complete balanced fertiliser at a low dose during active segment growth. Reduce nitrogen and overall dose as stems mature and buds form.

Red tips versus stressed tips

• Fresh tips show red pigmentation but stay firm: A red tint can be part of the selected plant’s normal new growth or increase under bright light. It is not rot when the tissue remains dry, firm and continues extending.
• Tips turn brown, soft or spread down the stem: That change is damage, not useful red colouring. Check for cold, trapped water or rot, cut back to clean green tissue and improve warmth and drainage.
• Stems wrinkle even though watering is frequent: Wet damaged roots may no longer supply the top. Slide the plant out and inspect before adding more water; reroot firm healthy sections if the root system has collapsed.
• Small cottony clusters lodge at stem joints: These cottony clusters are mealybugs. Isolate the plant, clean away what you can see, then treat the sheltered notches and base again as new insects emerge.

Keep Disocactus (Epiphyllum) ackermannii ‘Red tip’ away from children and pets

• Keep this plant away from children, cats and dogs.
• Its effects after chewing or swallowing are unclear, and plant material can still cause an upset stomach.
• Contact a veterinarian or medical professional if symptoms develop or do not settle.

What does Disocactus ackermannii mean, and who first published it?

Disocactus combines Greek dis, meaning twice, and isos, meaning equal, with cactus, referring to the two similar sets of floral segments. Ackermannii honours the German cactus grower Georg Ackermann, who brought the plant from Mexico to England in 1824.

John Lindley established the genus Disocactus in 1845 in Edwards’s Botanical Register, volume 31, plate 9.

Adrian Hardy Haworth first described it as Epiphyllum ackermannii in 1829 in Philosophical Magazine and Annals of Philosophy, new series, volume 6, page 109. Ralf Bauer later placed it in Disocactus as Disocactus ackermannii in 2003 in Cactaceae Systematics Initiatives, volume 17, page 16.