Give Your Garden a Seaweed Boost

Like a spring tonic, seaweed invigorates your plants and enriches your soil. Learn what it does, and how and when to apply it for best results

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by James CarrOctober 1999from exit # 23

The Aran Islands off the west coast of Ireland are windswept rock plateaus , nearly devoid of raw dirt , and yet there are garden everywhere , thanks to the merit of seaweed . For centuries the island-dweller have hauled loads of seaweed and sandpaper up from the beach and wedge both in fieldstone enclosures . There the seaweed and sand are composted with clay scraped from rocks . Over the generation , island-dweller have collected enough fertile dirt that their cautiously tend plot of land are able to supply the community ’s vegetable needs .

The agricultural use of seaweed has a prospicient story in coastal areas around the humankind . Even in regions endowed with plentiful soil , seaweed has been used successfully . In the 1950s , production of liquid seaweed concentrate start , providing inland gardeners with the benefits of seaweed . A liquefied dressed ore can be used to piss plants , but more important , it can be used as a foliar spraying .

Even the earth - locked can benefit from seaweed

Why does seaweed have such special properties ? The answer lies in the environment in which it lives . Most of the seaweed used horticulturally in the United States grows in the roiled coastal shallows of the northern Pacific Ocean and the northern Atlantic Ocean . Many of the earth ’s mineral are dissolved in sea piddle , and the agitated action of waves and current assures seaweed accession to all of them .

Most of the seaweed products sell in the United States for horticultural use are derive from the seaweedAscophyllum nodosum , commonly called knobbed sea wrack . A. nodosumcontains at least 60 elements , include many of those known to be essential for planetary plants : nitrogen ( N ) , phosphorus ( atomic number 15 ) , and potassium ( K ) , boron , Ca , copper , atomic number 26 , atomic number 12 , atomic number 42 , atomic number 16 , and zinc . Except for N and atomic number 19 , the amount of each of these lements in seaweed is quite minuscule . The amount need by plants is also relatively diminished , but it is vital . At best , deficiencies will take down productiveness ; at worst , plants will fade aside .

Although amounts change , dried A. nodosum typically contain from 1 to 1.5 percent nitrogen , 1.25 percent atomic number 19 , and only 0.2 percent daystar . Since seaweed is applied to plants in a highly dilute state , even the amount of NPK supplied is very small . Seaweed is not , therefore , a utter fertilizer .

But the benefit of seaweed go beyond supplying food . The ocean water that provides seaweed with nutrients also carry bacteria , viruses , and fungi . As a defense lawyers against these being , it is call back that seaweed synthesise an arsenal of chemic compounds , and these in turn can be used by garden plants . Seaweed also hurt harm from violent storm and scrounge nautical animate being , yet regrow rapidly . In fact , some seaweeds are rich in chemical compound have it away as plant growth regulators .

When seaweed is incorporate into soil or sprayed on leaves , plants engage its compounds for their own use . Seaweed promotes speedy , healthy ontogenesis and also stimulate the activity of bacteria that decompose filth particles into childlike nourishing compound that plant can readily take in . chelate compound in seaweed door latch onto these nutrients , preclude them from leaching out of the soil , yet readily releasing them to plant .

Composting seaweedSince I live near the shore , I gather seaweed from the beach and compost it . I always rinse off seaweed with fresh water before tote up it to the compost peck , so that salt does n’t build up in the soil . I mingle the seaweed with a lot of carbonous textile , such as leaves or straw , which will create air place call for for good oxygen catamenia through the compost . deficient oxygen will wrench the decay summons anaerobic , which will get the pile to breathe out an odor that will not soon be forget . Even with sound aeration , a sealed aroma will linger around the pile for several days . This can be controlled by covering the atomic reactor with several inches of carbon paper material , which also prevents the pile from getting too blistering . I wish to keep the great deal below 110 ° fluorine to prevent disintegration of the valuable organic chemical compound .

Those who plan to meet seaweed should obtain permission first . Most town have ordinances against removing natural stuff from beaches , though they ante up crews to take out seaweed . Whenever I ’ve asked the Parks Department for permission to remove seaweed , it has been most cooperative , as long as removal was done in an ecologically responsible personal manner . Never transfer seaweed from the urine ; only seaweed wash up on the beach should be collect .

If you’re able to not conglomerate seaweed , you’re able to buy seaweed repast , which is raw seaweed soil up and bagged . you’re able to lend the repast to your compost cumulation or turn it into your soil .

Using llquid seaweed class - roundI use seaweed with my first horticulture body process of the year — indoor come starting . After depositing seeds on the surface of stain block , I enshroud them with a thin layer of juiceless stain , moistened with a misting of limpid seaweed dilution . enquiry shows that fluid seaweed speeds up sprouting and increases the pct of seeds that germinate .

I have also found that the fungus - retarding property of seaweed suppresses damping - off disease . This first diligence of liquid seaweed , together with periodic tearing of the grow seedling with a seaweed dilution , assure the seedlings access to all the micronutrients they require , as well as to plant growth regulators . As an experiment , I grew two groups of seedlings , half of them process with seaweed , half without . The seaweed - treated seedlings grew importantly more rapidly , were more racy , and had sound root development . My observations have been verified by formal enquiry at Clemson University in South Carolina .

Arbico OrganicsPO Box 8910Tucson , AZ 85738-0910800-827-2847www.arbico.com

Gardener ’s Supply Company128 Intervale Rd . Burlington , VT 05401888-833-1412www.gardeners.com

Peaceful ValleyFarm SupplyP.O. Box 2209125 Clydesdale CourtGrass Valley , CA 95945888-784-1722www.groworganic.com

Liquid seaweed is sold as a dressed ore , which is then diluted with water . To avoid a establish - up of mineral , follow the manufacturer ’s instructions for diluting the dressed ore and for the frequence of app . Boron , for example , is essential to many industrial plant , in particular those in the cabbage family , but too much boron can be harmful .

The ledge life of dressed ore varies . Tony Ramsey , who manufactures Sea Cure , points out that if put in in a dry , cool , but not freeze , berth , the concentrate should retain its efficacy for at least two years . However , after being diluted , it eventually begins to degrade , so mix only what you involve for quick app .

Seaweed concentrate is also available in powder form . This is the least expensive way to purchase dressed ore , and it has an indefinite shelf living if stored under the same conditions advocate for the liquid dressed ore . It is potential , though , that the dehydration summons may disgrace some of the organic compounds .

If you live near the shore, harvesting your own seaweed can be just another gardening chore.Photo/Illustration: Linda Wesley

When I transfer my seedlings into the garden , they obtain a foliar sprayer of seaweed dilution . Plants are open to many variety of tension , not only international , like transplantation seismic disturbance , warmth , and drouth , but also inner , like blossoming and fruit stage set . When a plant is under stress , its metabolism boil down on its immediate selection motivation , while output of maturation hormones and compounds that guard off insects and disease declines . Seaweed foliar spray contains these of import compound . Applied to the leaves , they pass immediately through the folio stomate , the pore used for flatulency substitution , and are usable for immediate use . To cut down moisture loss , leafage stoma closely during the warmth of the day , so spray should be done in the sunrise or evening . I favour to spray towards evening so the dilution will stay on the leave through the cool , dampish night .

I routinely spray fruiting plants when they blossom , and again when they specify yield . I take advantage of seaweed ’s fungus - retarding dimension by spraying it on plants that are susceptible to mildew . It is thought that it retards the spread of mold by intervene with the generative activities of the fungus .

Seaweed is also reported to increase the bread message of industrial plant and their fruits , which leave in skillful frost protection . Seaweed may conquer the charge per unit at which a plant historic period , resulting in retentive life and great productivity . Seaweed may also increase the ledge life of fruits and vegetables , whether spray on them post - harvest , or render in liquid form to the uprise female parent plant .

I sometimes recall of the Aran Islanders as I trudge up from the beach , each hand convey a 5 - Imperial gallon pail tamp full of seaweed . They knew , intuitively or by geezerhood of observation , that seaweed ’s welfare were many . This knowledge is reinforced today , in my own garden . James Carr gardens on the rocky seacoast of Connecticut , where his garden reflects the bounty of land and ocean .

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