Troubleshooting
Theresa's Pincushion problems — and how to fix them
Theresa's Pincushion (Mammillaria theresae) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Root rot
The tiny root system is very sensitive to overwatering. Use the most free-draining mix possible and water with great caution.
Mealybugs
Mealybugs are difficult to see on such a small plant. Check the base of tubercles regularly with a magnifying glass and treat with alcohol swabs.
Failure to flower
A cool, dry winter rest period is mandatory. Keep at around 10°C with near-zero watering from October to February to ensure spring flowering.
Drying out too quickly
The small pot size means the soil dries rapidly in warm conditions. Check soil moisture more frequently in summer; the plant still needs water, just not standing moisture.
Loss from repotting damage
Handle this miniature with care when repotting. The small root system is delicate; repot carefully into only a slightly larger pot, ideally in spring.
Prevent theresa's pincushion problems before they start
Most theresa's pincushion issues are care-mismatch, not bad luck. Dial in the basics:
Theresa's Pincushion problems — FAQ
Why is my theresa's pincushion root rot?
The tiny root system is very sensitive to overwatering. Use the most free-draining mix possible and water with great caution.
Why is my theresa's pincushion mealybugs?
Mealybugs are difficult to see on such a small plant. Check the base of tubercles regularly with a magnifying glass and treat with alcohol swabs.
Why is my theresa's pincushion failure to flower?
A cool, dry winter rest period is mandatory. Keep at around 10°C with near-zero watering from October to February to ensure spring flowering.
Why is my theresa's pincushion drying out too quickly?
The small pot size means the soil dries rapidly in warm conditions. Check soil moisture more frequently in summer; the plant still needs water, just not standing moisture.
Why is my theresa's pincushion loss from repotting damage?
Handle this miniature with care when repotting. The small root system is delicate; repot carefully into only a slightly larger pot, ideally in spring.