Birthday
HydrangeasA floating garden is an island of plants that sits on the surface of a pond: the roots grow straight into the water while flowers and foliage rise above it. It brings a pond to life and gives fish shade and insects shelter. Here is where floating gardens exist around the world, which plants suit an island and how to build one yourself.
Plants for the garden and terrace are in our potted plants section.
Floating gardens around the world
- Dal Lake, Kashmir (India). For centuries locals have grown vegetables on floating beds made of compacted water plants and silt.
- Inle Lake, Myanmar. Floating beds anchored with bamboo poles, used among other things for growing tomatoes.
- Chinampas, Mexico City. The famous Aztec “floating gardens” do not actually float: they are artificial islands anchored in shallow water. Some chinampas in Xochimilco are still farmed today.
Which plants to use
Choose marginal and bog plants that tolerate permanently wet roots: yellow flag iris, water forget-me-not, marsh marigold, mint, sedges, arrowhead, flowering rush. Native species are the best choice.
Do not use water hyacinth or other invasive species where they could reach natural waters: water hyacinth is on the EU list of invasive species and can cover the entire water surface.
How to build a floating island
- Base. A ready-made floating pond module, or a DIY raft of closed-cell foam, plastic bottles or cork wrapped in coir netting.
- Planting pockets. Cut holes in the base and insert mesh aquatic baskets.
- Substrate. Heavy clay soil or aquatic compost topped with gravel so it does not wash out. Ordinary peat compost floats and clouds the water.
- Anchoring. Tie the island to an anchor on the bottom or to the bank so the wind does not push it around.
- Load. Plants get heavier as they grow, so allow spare buoyancy.
Care
- Plant roots take up some nutrients from the water, so an island may slightly reduce algae, but it does not replace a filter in a fish pond.
- Remove spent stems and dead leaves so they do not rot in the water.
- Thin out overgrown plants once a season.
- Islands with hardy plants can stay in the pond over winter or be pulled onto the bank; tender plants go into a cool room.
Design ideas
- Several small islands look more natural than one big one.
- On a small pond an island pairs well with water lilies — just keep at least half of the water surface open.
- You can make a floating bed in a barrel or large container on a balcony too.
FAQ
Will the island sink?
Not if the base is closed-cell material with spare buoyancy. Test it before planting by loading it with wet soil.
Can I grow vegetables on it?
Yes — that is what farmers on Dal and Inle lakes do. In a garden pond mint, watercress and salad herbs work well.
Is it harmful to fish?
No, a moderately sized island gives them shade and shelter. Just do not cover the whole water surface.
View full-size photo
Author: Maria Svitlovir
Graduated from Taras Shevchenko National University of Kyiv, Institute of Biology and Medicine (2001). BSc in Biology, MSc in Horticulture. Writes about plants, works at a garden centre selecting and repotting plants, and contributes to plant reference guides.
