Mammillaria hahniana (old lady cactus)

🌵 Care Guide

Mammillaria hahniana, commonly known as the Old Lady Cactus, is a beautiful seed-grown cactus admired for its small globular form and distinctive covering of white wool and pale spines. As the plant matures, the dense woolly covering gives it a soft, fluffy appearance. It is a relatively easy-to-grow species and a charming addition to any cactus collection.

☀️ Light

• Thrives in bright light with gentle direct sunlight.
• Morning sunlight for around 4–5 hours is ideal.
• Protect from intense afternoon sunlight during very hot summer weather.
• Indoors, place it near a bright east-facing window for good morning light.

💧 Watering

• Spring & Summer: Water thoroughly only when the soil is completely dry.
• Autumn & Winter: Reduce watering significantly and allow the plant to remain mostly dry.
• Always allow excess water to drain completely after watering.
• ⚠️ Avoid overwatering, as consistently wet soil can cause root rot.

🌡️ Temperature

• Prefers warm temperatures during the active growing season.
• Can tolerate cooler conditions when kept dry.
• Protect from frost and prolonged cold, wet conditions.

🌱 Soil

• Requires a porous, fast-draining cactus soil mix.
• A sandy or gritty mix is ideal for preventing excess moisture around the roots.
• Adding pumice, perlite, or coarse sand can further improve drainage.

🍽️ Fertilizer

• Feed once a month during spring and summer with a diluted, low-nitrogen cactus fertilizer.
• Do not fertilize during the winter resting period.

🪴 Potting

• Use a pot with excellent drainage holes.
• Repot when the plant outgrows its container, preferably during the active growing season.
• Handle the plant carefully to avoid damaging its delicate wool and spines.

🌸 Flowering

• Produces small, funnel-shaped pink to reddish flowers around the upper portion of the plant.
• Flowering generally occurs from late winter to early spring.
• Good sunlight, proper watering, and a cooler, dry winter rest can encourage flowering.

🌵 Appearance

• The plant has a small, globular form and may gradually form clusters of spherical stems.
• Dense white to off-white wool and pale spines give mature plants their characteristic “Old Lady” appearance.