Seaweeds are magnificent in their briny home. They are colourful, shapely, buoyant. Stranded by the tide, flaccidness takes over. The once-wafting blades and filigree become dismal heaps on the sand. If they remain piled up and begin to rot, their tangy smell of the sea intensifies to unpleasantness as sulphur compounds are released into the air. These fascinating organisms seem to have lost their raison d’être. Not so for the poet and artist Miek Zwamborn.

Zwamborn has made her home on the Isle of Mull, where she is alive to the fluctuating land- and seascapes. In her work, she seeks to straddle the artistic and scientific divide and she invites an eclectic range of collaborators to visit Knockvologan, where she has created a residential retreat with her partner. One day, on the shore nearby, Zwamborn found a freshly beached seaweed, twice her height in length, and carried it home. This, she writes, was the beginning of a new, immersive relationship with what the sea produces and offers to us creatures of the land.

Her exploration of seaweeds has taken Zwamborn far from the water. In herbariums, she examines flattened and dried specimens. Familiar with creating pressings herself, she marvels at the skill demonstrated by others in the processes of arranging, smoothing and preserving seaweeds. Among the textiles in the Victoria and Albert Museum she finds a worn seaweed-printed cotton dress bearing exquisite designs created by the 18th-century botanical artist William Kilburn. In the Matisse Chapel in Vence she watches colours and shapes appear on the floor as sunlight shines through the seaweed-inspired stained glass. She learns from a conversation with a compiler working on the Dicziunari Rumantsch Grischun, a dictionary of Rhaeto-Romanic, that the language contains only borrowed words for seaweed. High up in the Swiss Alps where this language lives, there is no sea and no seaweed.

Although seaweed has been a part of coastal diets for millennia, its status as a foodstuff is often forgotten. In the West, as foraging and subsistence were replaced by shopping and people left the seashore (or, as in Scotland, were driven from it by land clearances), land greens came to dominate. In Korea, Japan and China, seaweed consumption is still high and its health benefits renowned. We are all probably eating its extracts (useful for gelling and thickening) in many prepared foods, especially low-fat, low-calorie alternatives, but in the West seaweed consumption is generally confined to Asian or high-end foodie restaurants – another of those ironic developments that has seen a food once of the marginal become gourmet fare. Zwamborn is among the converts and includes illustrated recipes for several treats here, from simple breads and biscuits to more complicated dishes, such as a tempting cured mackerel fillet with crispy oarweed, oyster mayonnaise and pickles, served in a small pool of cold, clear kelp broth.

As well as its eaters, seaweed has its evangelicals. Farmed seaweeds can begin to close some of the loops in food production, a devastatingly polluting part of how we live today. Seaweeds can serve as sustainable fertilisers on land. They are also a means of mopping up the excess nitrogen created by fish and shellfish farms, leaving the water clearer and the fish healthier. A seaweed-derived supplement dramatically reduces the amount of methane emitted by cattle. Seaweeds can be used to create ethanol and other biofuels. But despite all these benefits, we need to remember that any intensification in the cultivation of a single crop has consequences.

We should be wary of manipulating the sea without due care and attention. Our knowledge of its complexities can best be described as evolving, and this extends to seaweeds themselves. Now defined as multicellular macroalgae, these organisms have not just been moved into different taxonomic groups as classifications change but undergone a shift from the plant kingdom to that of protists. Seaweeds are hard to depict well. To me, this serves as a metaphor for how difficult they are to pin down in the web of life and to access beneath the waves. Zwamborn meets the challenge head-on in her lovely illustrations, which invite the reader to touch the page, expecting to find something ‘brimming with life’ but coming away just with the feel of paper and a sense of wonder.