Gunnera can be propagated by division or by seed

Division

Prepare: Sterilize tools to prevent disease. 

Dig: Gently dig around the plant, being careful of the roots. 

Identify divisions: Find the natural divisions in the plant. 

Separate: Use a sharp tool to make clean cuts, ensuring each new section has roots and foliage. 

Replant: Move the new sections to a new location with fresh, well-draining soil. 

Water: Water well and keep the soil moist. 

Protect: Protect the new plants from harsh sunlight and frost damage. 

Seed

Harvest: Wait for the plant’s panicles to produce ripe, red fruits. 

Collect: Open the fruits over a container to collect the tiny black seeds. 

Sow: Lightly sow the seeds in a flat of moistened compost mixed with vermiculite or perlite. 

Germinate: Cover the tray with plastic or glass and place in a warm location. 

Transplant: Once the seedlings have germinated, transplant them to a new location with well-draining soil. 

Gunnera is a heavy feeder that needs lots of water and organic material. It can grow in full sun to partial shade, but it’s best to plant it in low ground near water.