Island growers turn seaward

Astonishingly rich in nutrients such as nitrogen, phosphorus and potassium, seaweed is highly valued on Inishmore, particularly for vegetable plots, writes FIONNUALA FALLON

ON THE ISLAND of Inishmore off the west coast of Ireland, the soil is sandy, porous and so very shallow that if you stick a spade in the ground, you're almost certain to hear the sharp crack of the blade as it hits solid limestone bedrock. Not, you might think, the kind of soil in which anyone could successfully grow potatoes or any other vegetables, but yet successive generations of the islanders have managed to do exactly that.

Their secret, as I saw for myself on a recent trip to Inishmore, isn't farmyard manure, garden compost or even sackfuls of expensive artificial fertilisers but instead very large quantities of fresh seaweed – or what the respected English vegetable gardener Charles Dowding calls "one of nature's most complete foods". Astonishingly rich in both major plant nutrients such as nitrogen (for leaf growth), phosphorus (for root growth), potassium (for flowering, fruiting and the plant's ability to withstand stress), as well as many of the numerous trace elements necessary to optimum plant health, these plant-like algaes have essentially allowed the Aran islanders to "make land" where once none (or very little) existed.

One seaweed that's particularly valued on Inishmore is the kind known botanically as Fucus serratus or "serrated wrack" but which the islanders themselves simply refer to as feamainn dhubh or "blackweed". A few weeks ago, I watched as Inishmore man Padraic Uí Neide expertly harvested heavy bucket loads of this algae from the island's stony shoreline, waiting until the "plants" were temporarily exposed by a low tide so that he could slice the warty, saw-toothed fronds from the damp rocks where they grow. The dripping seaweed was then transported by tractor across the beach and up along the road to one of the sloping, stone-walled fields where Uí Neide has his vegetable patch and where he used the seaweed as a perfectly balanced manure to make the lazy bed potato ridges (or what he calls iomaire) that are so traditional to the island.

But while blackweed is the seaweed of choice when it comes to making such ridges, it's by no means the only seaweed that the islanders use in their vegetable plots. "Sometimes we might spread a mulch of kelp on the beds during the wintertime; sometimes we'd use what we call feamainn dhearg or 'red weed'; sometimes we'd use a mix of different seaweeds including feamainn bhuí or 'yellow weed', says Uí Neide. "It really depends on what you're using it for." To prove his point, he took me on a stroll along the island's rocky beaches, where he pointed out a truly baffling array of different kinds of seaweeds that were either growing or had recently been cast up on the shoreline. These included kelps, wracks, dulses, carrageens and sea lettuces – some green, brown, yellow or red, some frilled, forked or even clawed.

Among them was the algae that many readers would know as bladderwrack, and which is also closely related to the islanders' blackweed. It's the very same seaweed that the Irish seaweed processing company Sea Nymph (sea-nymph-ireland.com) also hand-harvests in huge quantities from this country's southwest and west shorelines.

"We use bladderwrack – or Ascophyllum nodosum to give it its proper name – to make a range of different seaweed products for horticultural use," says Sea Nymph's export sales manager Stephen Casburn.

"It's packed full of nutrients and minerals that act as a general tonic or a 'pick-me-up' for plants." Casburn belongs to the third generation of Casburns involved in the seaweed business, the first being his English-born grandfather Cazzy Casburn who first came to Ireland back in the late 1940s as a chemical engineer investigating the possibility of setting up an alginate extraction plant.

Sea Nymph's range of seaweed products now includes liquid plant feeds, granular feeds, soil improvers and calcified seaweed while the company's contented clients include a host of golf courses and rugby/football clubs (Connacht Rugby, Ravenhill Stadium and Croagh Park among them). Their retail range of seaweed-based products has also been very successful with home gardeners (these are available through the Sea Nymph website or through Quickcrop (quickcrop.ie) ."

The Sea Nymph website also offers some other very interesting statistics on the many horticultural benefits of seaweed; for example, its use stimulates beneficial soil bacteria, improves soil structure, encourages plant cell division and aids in the transport of nutrients while very regular applications have even been proved to discourage parasitic nematodes.

Casburn is also keen to stress the fact that the company harvests its seaweed in the traditional way, by hand with a knife, in a sustainable fashion and with the proper permission from the relevant authority.

So if you love the idea of your garden enjoying the health benefits of this natural plant food but sadly don't live within easy distance of a beach, this range of Irish products may be just what's required.

DATE FOR YOUR DIARY:The ISNA April Plant Fair will take place tomorrow in the Festina Lente Walled Garden, Old Connaught Avenue, Bray, Co Wicklow. See isna.ie for details

Give lawns a revamp by tidying them up with a sharp lawn edger. Keep on hoeing and hand weeding

Sow nasturtiums, carrots, cabbage, peas, maincrop potatoes, plant onion sets. The Organic Centre in Leitrim stocks organically certified, sturdy young vegetable plants grown in a peat-free media (including some wonderful tomato varieties) for order through its website, theorganiccentre.ie

According to NUI Galway-based seaweed expert Prof Michael Guiry, the coastline of Ireland is home to an impressively rich diversity of seaweeds.

"So far, we've identified 580 different species of seaweed occurring along our coasts, and every year we discover something different. What's also fascinating is the fact that we've found that there are far more Irish names for the different kinds of seaweed than there are English – at the last count it was 87 versus 42," he says.

Many of these Irish names are listed in the book, Cladaí Chonamara, written by the Connemara-born botanist Séamus Mac an Iomaile while he recovered from TB in a New York hospital.

First published in 1938, it also contains his lovely ink drawings of some of the individual seaweeds that occur along the Connemara coastline.

An English translation by Padraic de Bhaldraithe (Shores of Connemara) was published by Tir Eolas in 2000.

Before you harvest

While what are termed "turbary rights" exist in regard to the harvesting of seaweed from the foreshore, anyone who can't prove ownership of such rights should contact the Department of the Environment for information on the licensing requirements. Small amounts of cast seaweed harvested for personal use would probably be exempt from this requirement. For more information on seaweeds and their various uses, see Michael Guiry's website seaweed.ie.

Prannie Rhatigan’s book Irish Seaweed Kitchen is also worth seeking out