PlantoscanImage: AI generated
New Zealand Pigmyweed Plant Care
Crassula helmsii (Kirk) Cockayne
Updated · Sources · How we source care data
With tiny, overlapping bright green leaves, this aquatic plant originates from Australia and New Zealand. Plant collectors are drawn to its ability to thrive in hard water conditions and form dense mats, making it a popular choice for water gardens and aquariums.
Every 7–14 days
Bright indirect
55–75°F
60–80%
At a glance
How do you care for New Zealand Pigmyweed?
Water New Zealand Pigmyweed every 7–14 days, letting the top layer of soil dry out between waterings, and give it bright indirect light. It prefers temperatures of 55–75°F (13–24°C) and 60–80% humidity. Fertilize it every month during the growing season. It is reported as toxic to pets, so keep it out of reach of pets.
Where Is the New Zealand Pigmyweed Native To?
What Is the New Zealand Pigmyweed?
New Zealand Pigmyweed (Crassula helmsii) belongs to the Crassulaceae family within the Crassula genus. New Zealand Pigmyweed is native to Southern Australia, Tasmania, New Zealand.
New Zealand Pigmyweed displays a floating, submerged growth habit, reaching up to tall with a spread of approximately 1 ft. New Zealand Pigmyweed produces small star-shaped flowers in clusters.
How Often Should You Water a New Zealand Pigmyweed?
Crassula helmsii requires watering every 7–14 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–14 days
Let soil partially dry between waterings
What Light Does the New Zealand Pigmyweed Need?
New Zealand Pigmyweed thrives in bright indirect light. Avoid placing New Zealand Pigmyweed in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect
What Temperature and Humidity Does the New Zealand Pigmyweed Prefer?
Crassula helmsii grows best at temperatures of 55–75°F. New Zealand Pigmyweed prefers humidity levels of 60–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
55–75°F
Humidity
60–80%
What Soil Mix Works Best for a New Zealand Pigmyweed?
Well-draining soil mix. Good drainage is essential for New Zealand Pigmyweed to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a New Zealand Pigmyweed?
Feed New Zealand Pigmyweed every month during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every month
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a New Zealand Pigmyweed?
Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a New Zealand Pigmyweed?
New Zealand Pigmyweed can be propagated through stem cuttings, division. Similar propagation techniques also apply to silver dollar plant plant care, which shares the same genus.
Is the New Zealand Pigmyweed Toxic to Pets and Children?
Toxic (caution)
Reported as toxic in our plant data. Not verified by the ASPCA.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the New Zealand Pigmyweed?
New Zealand Pigmyweed is susceptible to mealybugs, spider mites, scale insects. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the New Zealand Pigmyweed Need?
New Zealand Pigmyweed grows outdoors in USDA Zone 7a – 10b. It survives winters down to planting zone 7a. New Zealand Pigmyweed is native to Southern Australia, Tasmania, New Zealand.
Hardiness Zone
Zone 7a – 10b
Keep exploring plants
New Zealand Pigmyweed is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Crassula genus — compare its care with other Crassula species on PlantoScan.
Crassula is part of the Crassulaceae plant family — browse all Crassulaceae genera and species.
New Zealand Pigmyweed thrives in bright light and direct sun — see other bright-light plants.
More Crassula Species
Other Crassula species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Crassula helmsii (Kirk) Cockayne, family Crassulaceae (first published in Trans. & Proc. New Zealand Inst. 39: 349 (1907)) — World Flora Online record, IPNI name record.
- Pet toxicity: New Zealand Pigmyweed is reported as toxic to pets in our plant data (not verified by the ASPCA), so treat it with caution. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Photo: AI-generated illustration (labelled on the image).
- Hardiness zone: USDA Zone 7a – 10b, estimated from the plant's typical growing conditions.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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