
Photo: XufancCC BY-SA 4.0via Wikimedia Commonsresized / cropped
Indian Ironwood Plant Care
Gymnanthemum extensum Steetz
Updated · Sources · How we source care data
Gymnanthemum extensum, also known as bitterleaf tree, Chinese: 展枝斑鸠菊 zhan zhi ban jiu ju, Thai: หนานเฉาเหว่ย nan chao woei, is a species of flowering shrub of the family Asteraceae. It is an up to 8 m shrub or small tree found naturally growing at 1,200 m (3,900 ft) to 2,100 m (6,900 ft) above sea level in open forests or thickets in slopes, valleys and by the roadside.
Every 7–10 days
Bright indirect light
60–75°F
50–70%
At a glance
How do you care for Indian Ironwood?
Plant Indian Ironwood in bright indirect light (USDA zones 13a) and water a young shrub every 7–10 days until it is established. It tolerates temperatures of 60–75°F (16–24°C). Fertilize it every 6 months during the growing season.
What Is the Indian Ironwood?
Indian Ironwood (Gymnanthemum extensum) belongs to the Asteraceae family within the Gymnanthemum genus. Indian Ironwood is also known as Cacalia extensa, Conyza extensa, Eupatorium rufum.
Indian Ironwood displays an upright, bushy shrub growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Indian Ironwood produces small, daisy-like flowers in various colors.
Leaf size: approximately 6 inches.
How Often Should You Water a Indian Ironwood?
Water a young or newly planted Indian Ironwood every 7–10 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established shrubs mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.
Watering Frequency
Every 7–10 days
Until established; then in dry spells
What Light Does the Indian Ironwood Need?
Indian Ironwood thrives in bright indirect light. Avoid placing Indian Ironwood in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect light
What Temperature and Humidity Does the Indian Ironwood Prefer?
Gymnanthemum extensum tolerates temperatures of 60–75°F. Indian Ironwood prefers humidity levels of 50–70%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
60–75°F
Humidity
50–70%
What Soil Mix Works Best for a Indian Ironwood?
Well-draining, loamy soil with added perlite for improved drainage. Good drainage is essential for Indian Ironwood to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Indian Ironwood?
Feed Indian Ironwood every 6 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established shrubs in good soil often need little extra feeding, so let weak growth or pale foliage guide you.
Stop feeding by late summer so new growth can harden before winter.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
Where Should You Plant a Indian Ironwood?
Choose a spot with bright indirect light and well-draining, loamy soil with added perlite for improved drainage. Avoid low spots where water collects after rain.
Indian Ironwood is suited to USDA Zone 13a.
Plant container-grown or balled-and-burlapped shrubs in spring or early autumn, setting the root flare at soil level, and water well after planting.
How Far Apart Should You Plant a Indian Ironwood?
Indian Ironwood can spread to about 2 ft (0.6 m) and reach about 3 ft (1 m) tall. Space plants about 2 ft (0.6 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.
Planning a row or hedge? Try the plant spacing calculator.
How Do You Prune a Indian Ironwood?
Prune Indian Ironwood while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.
If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the shrub in one year.
How Do You Care for a Indian Ironwood in Winter?
Indian Ironwood is frost-tender (hardy to USDA zone 13). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.
How Do You Propagate a Indian Ironwood?
Indian Ironwood can be propagated through stem cuttings, division. Similar propagation techniques also apply to wild coffee plant care, which shares the same genus.
Is the Indian Ironwood Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Indian Ironwood, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
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 Indian Ironwood?
Indian Ironwood is susceptible to aphids, spider mites, whiteflies. 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 Indian Ironwood Need?
Indian Ironwood grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. In cooler regions, grow Indian Ironwood as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Indian Ironwood 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 Gymnanthemum genus — compare its care with other Gymnanthemum species on PlantoScan.
Gymnanthemum is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Indian Ironwood thrives in bright light and direct sun — see other bright-light plants.
Related Plant Care Guides
Closely related plants with similar care requirements:
Sources
- Scientific name & taxonomy: Gymnanthemum extensum Steetz, family Asteraceae (first published in Naturw. Reise Mossambique 6(Bot., 2): 337 (1864)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Indian Ironwood, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Photo: Xufanc, CC BY-SA 4.0, Wikimedia Commons — original.
- Hardiness zone: USDA Zone 13a, calculated from the plant's minimum temperature.
- 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.
