Kroenleinia grusonii: hedgehog cactus or mother-in-law's cushion?
Kroenleinia grusonii
- Exposure
- Sun
- Hardiness (USDA)
- 11a (4.4°C ≤ T° < 7.2°C)
- Lifecycle
- Perennial
- Foliage
- Deciduous
- Family
- Cactaceae
- Genus
- Kroenleinia
- Species
- Kroenleinia grusonii
Other names:Echinocactus corynacanthus, Echinocactus galeottii, Echinocactus grusonii
You can't sit on that cushion! Nicknamed the “mother-in-law's cushion,” Kroenleinia grusonii is a cactus native to Mexico. While its rounded shape makes it look like a pouf, its golden spines would deter anyone from sitting on it.
How can you recognize Kroenleinia grusonii, the “mother-in-law's cushion”?
Kroenleinia grusonii is a plant with a spherical shape. It grows slowly but can reach 1.5 meters in height and 1 meter in diameter.
At first glance, Kroenleinia grusonii resembles a light green ball. It is actually composed of about thirty narrow ribs. The apex, like the ribs, is covered with areoles. Each areole bears golden-yellow or white spines that are five centimeters long.
The yellow flowers appear only on cacti over 20 years old. As with parodia lenninghausii, they develop at the top of the plant and form a distinct circle. The summer blooming period lasts only three days.
The globular fruits measure between one and two centimeters long. Greenish in color and covered with white fuzz, they contain numerous small, shiny, dark brown seeds.
The mother-in-law's cushion is not toxic, but its sharp spines require extra caution around pets or young children. Also, be sure to wear thick gloves to avoid injuring your hands when handling the plant.
Our care tips
Your plant needs watering in winter only when the temperature is above 18°C. If it spends the off-season outdoors or in an unheated greenhouse, one watering every two months will be more than enough.
Watering
When the soil is dry on the surface, for about five centimetres, water generously, but without flooding the pot. Use non-calcareous water, such as rainwater. If you don't have any, you can use tap water that has been left to stand for 24 hours. Always ensure that the water is at room temperature.
As with most plants, stagnant water causes roots to rot. If your Stepmother's cushion pot is on a saucer, empty it after watering. If your plant is too large to be moved, raise the pot above the saucer (by placing it on gravel or clay balls) or remove the saucer.
Misting
Your Kroenleinia grusonii hates wet foliage. Don't mist the plant.
Repotting
In spring, transfer your Kroenleinia grusonii to a larger pot, so that it can continue to grow.
Fill the bottom of a perforated pot with potting soil for cacti and succulents.
Put on a pair of gloves to protect yourself from thorns. Plant your Stepmother's cushion in the center and add potting soil. Stop filling the pot a few centimetres from the edge to form a watering basin.
Wait at least a fortnight for your plant to root before watering.
Fertilization
You can stimulate the development of your plant during its growth phase, in spring and summer, with fertilizer.
You don't have to fertilize your plant to make it grow. However, if you want to stimulate its growth, you can give itfertilizer for cacti and succulents.
Planting
Once the last spring frosts have passed, you can plant.
Your Stepmother's cushion fears humidity. Plant it in a place where water doesn't stagnate, at the top of a slope, an embankment or in a rockery, for example.
Dig a hole slightly larger than the root ball. You can place pebbles or clay balls at the bottom to improve drainage. Then lay down a layer of substrate. If your soil is light and chalky, you can use garden soil. If your soil is rich and heavy, use potting soil for cacti and succulents.
Plant your Stepmother's cushion and fill in with garden soil or substrate. Water to remove air bubbles and encourage rooting.
Taking cuttings
Cutting is carried out during the strong growth phase, generally in spring and early summer.
After a few years, your Stepmother's cushion produces shoots. You can divide them to multiply the plant.
Once the plant has been dug up, separate one of the shoots, with its roots. Beware of thorns! Remember to wear gloves when handling your Stepmother's cushion.
Obtain a pierced pot adapted to the size of your cutting. Fill it with a light, draining substrate, such as a mixture of sand and potting soil for cuttings, or potting soil for cacti and succulents. Plant your Kroenleinia grusonii and tamp it down.
The substrate is already damp and kroenleinia grusonii dislikes excess water. Wait at least a week before watering.
Diseases / Threats
Information
- Lifecycle
- Perennial
- Foliage
- Deciduous
- Exposure
- Sun
- Substrate
- Calcareous earth
- Planting methods
- Open groundIn potsIn tubs
- Category
- Indoor
- Tags
- BeginnerHard to kill
- Origin
- Central America
- Hardiness (USDA)
- 11a (4.4°C ≤ T° < 7.2°C)
- Leaf color
- Light green
- Flower color
- Yellow
- Fruit color
- Light green
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Find out more
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