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Gardens Love Seaweed

Posted in Garden Advice on February 07, 2018

Seaweed Fertiliser and Mulch 

Seaweeds are the plants of the sea. Seaweed has been used as fertiliser and soil tonic for hundreds and thousands of years. They may not have high levels of nitrogen and phosphorous but they are a rich source of trace elements and micro-nutrients. They are a tonic for your soil; correcting soil deficiencies that would adversely affect the balance of soil micro-organisms and consequently the availability of nitrogen and other macro-nutrients for your plants.

Seaweeds break down easily in the soil because, unlike most land plants, they do not contain tough lignin and high levels of cellulose that are resistant to breakdown. They do contain complex carbohydrates that soil fungi and bacteria can feed on. These soil micro-organisms are essential for the efficient uptake of nutrients by plant roots. These beneficial organisms also play a role in preventing disease-causing organisms infecting the soil and plants.

There is evidence that plant hormones in seaweeds promote chlorophyll production, root growth and germination of seeds.

Seaweed is a good source of iodine and selenium which when used on fruit and vegetables adds to the nutritional value of the crops. This is particularly important as iodine and selenium are deficient in New Zealand soils and consequently in our diet.

Growing up I always lived by the sea. My siblings and I spent many hours collecting seaweed that had been washed ashore for application to our family garden; I do not recall my parents ever buying fertiliser. The resulting garden was a spectacular profusion of colours and thick green vegetation; which is no mean feat when the garden is on the shore of the Irish Sea! The garden was so good it was opened to the public and was the feature of a full half-hour programme (How Does Your Garden Grow) on national British television.

Kiwicare Gro-Sure Planting Magic contains seaweed as one of the organic matter constituents. Planting Magic is a 4 in 1 planting mix which provides the essential nutrients for plant establishment and season-long vigorous growth. It improves water and nutrient retention around root systems, improves soil condition and beneficial micro-organisms and boosts root development.

Benefits and Features

  • Bigger, Healthier Plants!
  • Add Planting Magic around the root ball of bedding plants, vegetables, trees and herbaceous plants
  • Fertiliser:
    • Immediately available for promoting plant establishment
    • Slow-release for ongoing healthy growth
    • N:P:K approx.* 5 : 2.5 : 3.5 plus S (2.8), Fe (0.4), Mn (0.1) and other trace elements.
  • Organic matter:
    • Humus and humic acids
    • Micro-nutrients
    • Improves soil condition and beneficial micro-organisms
  • Water retention:
    • Porous baked clay granules hold water at 100% w/w
    • Organic humus also improves water and nutrient retention

 *No data for the naturally variable organic matter.

David Brittain


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