Silver Ball Cactus

Silver Ball Cactus (Parodia scopa) is a neat globe of a cactus, densely covered in fine silvery white spines that catch the light from any angle. It reaches only about 250mm tall and 150mm across, which makes it a lifetime resident of a single decent pot. Glossy yellow flowers open around the crown in the warmer months.

Why you'll love it

• The silver is unusual. Most cacti read grey green. The dense white spination here gives a genuinely silver plant.
• Glossy yellow flowers. Mature plants ring the crown with bright yellow flowers through the warm months, a real display on a plant this size.
• It stays small for life. At 250mm by 150mm you are not repotting into ever larger containers.
• Drought tolerant and unfussy. Poor soil suits it and it survives long stretches without water. The one thing it will not tolerate is staying wet.

Where it works best

Pots, balconies and courtyards. A 150mm to 200mm pot in a gritty cactus mix will do this plant for many years. A hot west facing balcony that cooks other plants is ideal.

Rockeries and gravel gardens. Tucked among stones it gets the sharp drainage and reflected warmth it evolved for, and it needs no irrigation once established.

Indoors, in the brightest spot you have. It will live indoors, but only against a north or east facing window. Away from strong light it grows soft and elongated instead of round.

Growing Silver Ball Cactus in Australia

Position and climate. Full sun outdoors, or the brightest available window inside. It suits warm temperate, subtropical, Mediterranean and arid to semi arid gardens, and tolerates light frost only. In cool temperate and frost prone gardens, grow it in a pot that can move under cover for winter.

Soil. A proper cactus and succulent mix, or potting mix cut by half with coarse sand and gravel. The pot needs a drainage hole, and lean soil produces the best spination.

Water. Soak thoroughly, then let the mix dry right through before the next drink: roughly every two to three weeks through the warm months. From late autumn to early spring keep it almost completely dry. Cold and wet together is what kills cacti, not cold on its own.

Feed, repotting and spines. A low nitrogen cactus fertiliser once or twice through spring and summer supports flowering, and fresh mix every three or four years keeps it going. The spines are fine but sharp, so keep it back from a doorway and away from children and pets.

What to expect when it arrives

Silver Ball Cactus is sold as tube stock, so you receive a young plant, generally 30mm to 60mm across. This is a slow growing cactus: expect two to three years of steady growth before it takes on the full round form, and similar patience before the first flowers.

Cacti travel better than almost anything else we send. Leave yours dry and out of direct midday sun for the first week, then pot it on and begin normal watering. Plants are delivered Australia wide, with delivery from $29.95. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• Browse the full cactus range
• Read about low maintenance cacti for a front facade
• See what else suits a dry bed in our rockery plant collection
• Find companions among plants that suit pots

Common questions

How often should I water it?

Every two to three weeks in the warm months, and only once the mix is dry all the way through. Through winter, water barely at all.

When will it flower?

Once the plant reaches a reasonable size, usually two or three years on from tube stock. Full sun through the previous season is what sets the flowers.

Can it live indoors permanently?

Yes, provided it sits directly at a bright window. In average room light it stretches into a soft elongated shape, and that growth never rounds up again.