Large-flowered Poison Pea Plant Care
Gastrolobium grandiflorum F.Muell.
Updated · Sources · How we source care data
Gastrolobium grandiflorum, commonly known as wallflower poison, wallflower poison bush or heart-leaf poison bush, is a bushy shrub which is endemic to Australia.
Every 7–14 days
Full sun to partial shade
60–80°F
40–60%
At a glance
How do you care for Large-flowered Poison Pea?
Plant Large-flowered Poison Pea in full sun to partial shade (USDA zones 13a) and water a young shrub every 7–14 days until it is established. It tolerates temperatures of 60–80°F (16–27°C). Fertilize it every 6 months during the growing season. It is reported as toxic to pets, so keep it out of reach of pets.
Where Is the Large-flowered Poison Pea Native To?
What Is the Large-flowered Poison Pea?
Large-flowered Poison Pea (Gastrolobium grandiflorum) belongs to the Fabaceae family within the Gastrolobium genus. Large-flowered Poison Pea is native to Australia. Large-flowered Poison Pea is also known as Mountain Poison Pea.
Large-flowered Poison Pea displays an upright, bushy shrub growth habit, reaching up to 4 ft tall with a spread of approximately 3 ft. Large-flowered Poison Pea produces brightly colored pea-like flowers in clusters.
Leaf size: approximately 2 inches.
How Often Should You Water a Large-flowered Poison Pea?
Water a young or newly planted Large-flowered Poison Pea every 7–14 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 7–14 days
Until established; then in dry spells
What Light Does the Large-flowered Poison Pea Need?
Large-flowered Poison Pea thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Large-flowered Poison Pea Prefer?
Gastrolobium grandiflorum tolerates temperatures of 60–80°F. Large-flowered Poison Pea prefers humidity levels of 40–60%.
Temperature
60–80°F
Humidity
40–60%
What Soil Mix Works Best for a Large-flowered Poison Pea?
Well-draining sandy loam with added organic matter. Good drainage is essential for Large-flowered Poison Pea to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Large-flowered Poison Pea?
Feed Large-flowered Poison Pea 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 Large-flowered Poison Pea?
Choose a spot with full sun to partial shade and well-draining sandy loam with added organic matter. Avoid low spots where water collects after rain.
Large-flowered Poison Pea 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 Large-flowered Poison Pea?
Large-flowered Poison Pea can spread to about 3 ft (0.9 m) and reach about 4 ft (1 m) tall. Space plants about 3 ft (0.9 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 Large-flowered Poison Pea?
Prune Large-flowered Poison Pea 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 Large-flowered Poison Pea in Winter?
Large-flowered Poison Pea 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 Large-flowered Poison Pea?
Large-flowered Poison Pea can be propagated through seeds, cuttings. Similar propagation techniques also apply to gastrolobium acrocaroli plant care, which shares the same genus.
Is the Large-flowered Poison Pea Toxic to Pets and Children?
Toxic (caution)
Reported as toxic in our plant data. Not verified by the ASPCA.
Toxic to humans and pets
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 Large-flowered Poison Pea?
Large-flowered Poison Pea is susceptible to aphids, caterpillars, spider mites. 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 Large-flowered Poison Pea Need?
Large-flowered Poison Pea grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Large-flowered Poison Pea is native to Australia. In cooler regions, grow Large-flowered Poison Pea as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Large-flowered Poison Pea 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 Gastrolobium genus — compare its care with other Gastrolobium species on PlantoScan.
Gastrolobium is part of the Fabaceae plant family — browse all Fabaceae genera and species.
Large-flowered Poison Pea thrives in bright light and direct sun — see other bright-light plants.
More Gastrolobium Species
Other Gastrolobium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Gastrolobium grandiflorum F.Muell., family Fabaceae (first published in Fragm. 3: 17 (1862)) — World Flora Online record, IPNI name record.
- Pet toxicity: Large-flowered Poison Pea 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.
- 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.
