Light
Filtered Sun
Thrives in bright, filtered sunlight; protect from harsh, direct midday summer sun to prevent scorching.
Reference image 
Reference image Discocactus fariae-peresii
Faria-Peres' Disc Cactus
Overview
Discocactus fariae-peresii is a highly coveted, endangered globose cactus belonging to the family Cactaceae 1. Endemic to the seasonal dry tropical regions of Brazil, it is characterized by its flattened globose stem, strong spination, and the distinctive cephalium at the crown from which nocturnal, highly fragrant white flowers emerge.
Taxonomy and Naming
Belonging to the genus Discocactus, this species represents a relatively recent addition to the formal botanical literature. Taxonomists identified and described this species based on distinct morphological characteristics, separating it from closely related taxa within the Brazilian central plateau 2.
Distribution and Habitat
This succulent subshrub is native to Brazil, specifically recorded in Distrito Federal, Mato Grosso, Mato Grosso do Sul, and Goiás. It thrives in seasonally dry tropical biomes, often growing in rocky savannas (cerrado), quartzite outcrops, and gritty, nutrient-poor mineral soils 1.
Appearance
The body of Discocactus fariae-peresii is solitary, depressed-globose, and features well-defined ribs. Sharp, curved spines emerge from woolly areoles along the ribs. Upon reaching maturity, the apex produces a dense, woolly cephalium. From this cephalium, large, funnelform white flowers bloom at night to attract specialized pollinators.
Culture and Care
This species is notorious among growers for being extremely sensitive to overwatering and root rot. It requires a highly mineral substrate and is often cultivated as a grafted plant on robust rootstocks to bypass its fragile root system. Filtered sun and high temperatures are essential.
Common Mistakes
The most prevalent issue is root decay caused by organic-rich soils, poor drainage, or cold-moist winter conditions. Inadequate ventilation also invites pests.
Bibliography
References
Watering
10-30 Days
Water sparingly in summer only after the soil has completely dried; keep completely dry during winter.
Soil
Highly-drained, mineral-rich, quartz-heavy cactus soil mix
Requires an almost purely mineral mix of pumice, quartz grit, and volcanic rock with negligible organic content.
Safety
Pet Friendly
Equipped with sharp spines; handle with care using gloves or specialized tongs. Non-toxic to pets.
Difficulty
Hard
Very challenging due to its extreme sensitivity to overwatering, high cold-sensitivity, and fragile roots.
Native Habitat
Brazil (Distrito Federal, Goiás, Mato Grosso, Mato Grosso do Sul)
Indigenous to the central-western highlands of Brazil, where it grows in seasonally dry tropical climates, colonizing shallow pockets of quartz sand among rocky outcrops.
Frequently Asked Questions
Can Discocactus fariae-peresii be grown indoors?
Yes, but due to its high light and temperature requirements, it is best kept on south-facing windowsills or under dedicated grow lights.
How often should this cactus be watered?
Water roughly every 10 days in summer when the soil is completely dry, and limit watering to once a month or not at all during winter to prevent rot.
How can I prevent root rot?
Prevent root rot by using a purely mineral soil mix rich in quartz sand and pumice, and never allowing water to sit in the drainage saucer.
What type of soil should be used?
Use a specialized cactus mix mimicking its natural habitat, containing 80-90% pumice, quartz grit, and volcanic rock, with minimal peat.
When does it bloom and what are its flowers like?
It blooms in summer from the mature apical cephalium. The flowers are white, open at night, and emit a very strong, pleasant fragrance.
What temperature is required in winter?
During winter dormancy, the temperature should not fall below 12°C. Cold and damp conditions are fatal to this species.
Should it be grown on its own roots or grafted?
Growing it on its own roots is highly challenging; for beginners and intermediate growers, grafted specimens are strongly recommended.
How fast does it grow?
It is a very slow-growing cactus. It takes several years to develop its cephalium and reach blooming maturity.
Is it toxic to pets?
It does not contain toxic compounds and is safe for cats and dogs, though its sharp spines can cause physical injury.
What is a cephalium?
A cephalium is a specialized, woolly, and densely spined reproductive structure that forms at the apex of mature cacti, from which flowers and fruits emerge.