This spectacular perennial is native to South American cloud forests are well at home in many temperate gardens. This plant is huge with thick leaves reaching over 1m across held by very sturdy stems. Also known as “Dinosaur Food” for its primitive appearance. Need even moisture and deep humus rich acidic soils.
Three year old plants are massive, so plan accordingly. Considered hardy in Zone 7, Gunnera grown in Zones 7-8 need special care in order to survive winters by cutting down all of its leaves in late October to 30 cm of the root ball, use the leaves to make a tent to shed water from the crown. Some folks use a thick layer of dry mulch instead of leaves over the crown for the winter. If so, the mulch should be kept dry by a tarp or other rain proofing material. Remove mulch/leaves when last spring frost is past
Those pushing the envelope in colder climates are better off growing in pots and dragging them into a freeze-free greenhouse to over winter.
- Seed Count: 1 gram
- Collection Date: Oct 2020
- Hardiness Zone: 7-10
- Height and Width: 3m x 3m (or more)
- Germination test type: hand sort
- Family: Gunneraceae
How to germinate Gunnera seeds:
Sow thinly at 2mm in pots of well draining humus rich medium. Mist daily. A clear plastic cover will help retain humidity. Germinate 25-27°C. Do not over water. Seed will germinate in 30 to 90 days. Seedling can grow to a decent size in a short time possibly out competing its smaller and yet-to-germinate siblings.
One germination technique we use is:
Sprinkle seed on moist unbleached coffee filter placing seed some distance apart from each other so you have room to prick out the seedlings when they emerge. Fold coffee filter and place in a resealable baggie. Give light and gentle warmth. Check in 14 days and prick out seedlings and transplant in moisture retentive medium.