Giant rhubarb
Gunnera manicata · Gunneraceae
📷 Required attribution is: Photo by Tom Oates.The original uploader was Nabokov at English Wikipedia. (a.k.a. Tom Oates) · CC BY-SA 3.0
⚠️ Poils des feuilles et des pétioles causent dermatite de contact irritative chez humains sensibles.
The gardener's calendar
Ideal time to plant giant rhubarb: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Common name
- Brazilian Gunnera
- Family
- Gunneraceae
- Plant type
- Herbaceous perennial
- Adult height
- Up to 1.8 m
- Foliage
- Deciduous
- Flowering
- May to July
- Hardiness
- Frost-sensitive (protected temperate zones)
- Origin
- South America (Brazil)
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability high.
Expert tips
The key tip
Plant in very rich, consistently moist soil (avoid waterlogging) in part shade. Divide every year after flowering to rejuvenate and contain.
The common mistake
Planting in dry soil or too much shade: growth slows, foliage yellows, and those massive leaves never reach their full potential.
The pro's trick
Install light drip irrigation in dry or continental zones: regular watering from May to September is low-effort and makes a real visual difference with this giant plant.
Care
Watering
Gunnera demands constantly moist, almost marshy soil, but without prolonged water stagnation. Water regularly and generously during the growing season (spring and summer). In winter, reduce watering but never let the soil dry out completely.
Light exposure
Position the plant in part shade or partial shade. It tolerates shaded areas and particularly appreciates afternoon shade in very hot climates. Full sun exposure can scorch its immense, delicate leaves.
Soil
Gunnera thrives in fertile, organic-rich soil that drains well. Prepare a mixture enriched with compost or peat to maintain moisture. Adding organic matter promotes spectacular foliage development.
Fertilizing
Apply a balanced or nitrogen-rich fertilizer in spring and early summer to support its very vigorous growth. Moderate monthly fertilization is sufficient. Favor adding well-decomposed compost in autumn.
Pruning and maintenance
Little pruning is necessary. Simply remove damaged or dead leaves. In autumn, cut back the plant at soil level if it goes dormant in cold climates, or remove dried leaves at the base.
Diseases and pests
Watch for aphids and slugs that enjoy tender young leaves. Excessive moisture can promote root rot; ensure good drainage. No major disease affects it if growing conditions are properly maintained.
Did you know?
Brazilian gunnera is renowned for having some of the largest leaves in the angiosperm world: they can exceed 2 to 3 meters in diameter with robust petioles covered in protective bumps. Its spectacular flowering produces a compact reddish spike that is highly original. This plant was once used as a botanical curiosity in Victorian gardens throughout Europe.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- PigvineGunnera magellanica
- Giant rhubarbGunnera tinctoria
- GrapevineVitis vinifera
- CamelliaCamellia japonica
- Pedunculate oakQuercus robur
- SageSalvia officinalis
Tips generated and checked by Viridia — adapt them to your local climate.