Parodia leninghausii is a species of South American cactus commonly found as a houseplant. Common names include Lemon Ball cactus, Golden Ball cactus and Yellow Tower cactus.
Parodia leninghausii is endemic to Rio Grande do Sul, Brazil. It occurs at elevations of 300-1300 meters above sea level. This species grows in hilly grassland and on walls between cracks in the rocks or in the shade of larger growing plants in pine forest. This species is abundant where it occurs. Many of its subpopulations have been extirpated. It grows in one of the most temperate region of the countries with warm and cool seasons and weather can become very cold during the winter nights, often it will fall to just above freezing without harming the plants as it is also very dry. The soil there is well drained and has a fairly high organic content, derived from the decomposition of other plants.
In the growing season, the plants should be watered at least once a week. When watering, the soil should be given a good soaking, allowing excess water to drain away. Allow the compost to dry out slightly between each watering.
In most cases, plants receiving no outdoor light should be lit from 16 to 18 hours each day. If some additional light is received, 12 to 14 hours each day may be adequate. Lights should be used at the same time that plants receive window light.
Most often planting instructions will suggest planting in loam soil. Loam soil should be rich in minerals and nutrients for the plants and loose enough that roots and spread out and grow strong.
Cacti fertilizer requirements are pretty simple. Any good houseplant food (diluted to half) that's higher in phosphorus than nitrogen is a good choice. A 5-10-5 solution can work well.
By removing overgrown foliage, you will improve airflow to the plant, and light will be better able to penetrate all portions of the plant. This actually leads to a fuller and healthier looking houseplant.
The plant is frost tolerant as low as -4°C (or possibly colder) but in cultivation it is best to avoid any frost when during the winter the temperature can go down to 2°C without any harm so long as the compost is very dry. During the summer it is best to keep the plants outside where the temperature can rise to over 30°C with no harm to the plant.
Many seasoned gardeners recommend using a container that is about 10% larger in diameter than the cactus plant at its widest point.