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Liquid Seaweed Fertiliser

One of the best fertilizers you can use on your plants is liquid seaweed, yet this is probably the last fertilizer people think of buying when they go to their local garden centre or shop online. Liquid seaweed fertilizer is not only organic, but comes from a sustainable source and can be harvested without damaging the environment.

Most seaweed based fertilizers are made from Kelp, a variety of seaweed which can grow to lengths of over 50 metres. Trace elements found in seaweed organic fertilizers include magnesium, potassium, zinc, iron, and nitrogen — all of which are beneficial to plants. Nitrogen, for instance, is essential to the production of nitrate, a key component needed by plants during photosynthesis.

In the Channel Islands, such seaweed fertiliser is known as vraicin their dialects of Norman, a word that has also entered Channel Island English, the activity of collecting vraic being termed vraicking. In Scotland, it is used as fertiliser in lazybeds or feannagan.

Falkland Islanders have also been nicknamed “Kelpers” from time to time, from collecting seaweed partly for this purpose.

Fermenting Seaweed

Great for lawns or golf courses

One benefit of using a liquid seaweed fertilizer is that you can vary the concentrations according to what you are using the fertilizer for, so for instance, on a lawn you would probably use a more diluted mixture, but for a houseplant you would tend to use a stronger concentration. One thing I have noticed is that a little of this product goes a very long way with some pretty impressive results. Personally one of my favourite uses for liquid seaweed fertilizer is to give my exhibition vegetables a boost during the growing season in the hope I will stand a better chance of securing a few prizes once the Summer show comes around each August.

Foliar application is no doubt the most efficient and effective method of administering liquid seaweed to your plants . Kelp extracts are 8 to 20 times more effective when applied to the leaves then when broadcast on the soil. Spray as a fine mist until it drips off the plants’ surfaces and the plants will immediately absorb the fertilizer and begin to benefit from it by the second day.

Liquid seaweed fertilizer is used by many of the English and Scottish Football Premiership Grounds, as well as numerous UK Championship Golf Courses. In fact the high number of quality top sporting venues that use liquid seaweed extract as a fertilizer prove that it is extremely effective as a plant food.

Advantages of Using Liquid Seaweed Fertilizer

  • It promotes additional buds when applied as the plants are beginning to bud.
  • It extends the shelf life of fruits and vegetables if applied 10 days before harvesting
  • It lengthens the life of cut flowers if they are sprayed with Liquid Seaweed a day or two before cutting.
  • Treating seeds or seed pieces with Liquid Seaweed prior to planting will improve seed germination, root growth, and early seedling vigor.
  • Liquid Seaweed also can be used as a rooting solution. Place cuttings in a solution of Liquid Seaweed and water until roots develop, then plant. When planting, water in with Liquid Seaweed solution.
  • Liquid Seaweed applied to pasture crops increases the nutrient uptake, the protein content, and overall quality of the crop.
  • Seaweed organic fertilizers can be used as a soil treatment to grow healthier, stronger, and more disease-resistant plants.
  • A wide range of beneficial effects have been reported from the use of liquid seaweed extracts including increased crop yields, resistance of plants to frost, increased uptake of inorganic constituents from the soil, more resistance to stress conditions and reductions in storage losses of fruit.
  • Promotes vigorous growth and helps deter pests and diseases on fruit, flowers, vegetables, lawns etc.
  • Seaweed has more than 70 minerals, vitamins, and enzymes.
  • Seaweed fertilizers are especially useful in organic gardening. They contain almost every micro-nutrient in a fully chelated (immediately available) form. They deliver a healthy dose of natural plant hormones. Seaweed is full of carbohydrates, which the plants use as a building block and which large populations of beneficial micro-organisms use as a food source.
  • Alginates, (sponge-like starches found in seaweed), hold water droplets near the plant roots, making moisture available to them without drowning them; they also help enrich the soil by feeding myriad beneficial microorganisms such as bacteria and tiny fungi necessary to composting.
  • Research at major universities has shown that seeds soaked in seaweed extract germinate more rapidly, have larger root mass, stronger plant growth and higher survival rate. Soaking plant roots in seaweed extract reduces transplant shock and speeds root growth.
  • Several university studies have shown that seaweed can produce dramatic results in plants: geraniums produced more flowers per plant; grapes were sweeter; gladiolus corms grew larger; and cucumber yields increased 40 percent and the fruits suffered less often from softening and rotting. Improved yields after seaweed treatments were measured in potatoes, sweet corn, peppers, tomatoes, apples, strawberries, okra, and oranges. Better frost tolerance, increased seed germination, and greater capacity to absorb trace elements were other documented benefits for plants.
  • Seaweed fertilizers have many benefits. They provide natural hormones and many nutrients not found in other forms of fertilizer. Since most plants absorb their nutrients through the leaves, applying this with a foliar method will benefit the plant even more. Foliar simply means placing the fertilizer on the leaf itself. As the plant absorbs the sunlight it needs, it will also be absorbing the nutrients found in the fertilizer.
  • Another major component in liquid seaweed fertilizers are the hormones. The main hormones in seaweed are auxins, gibbelerins, cytokinins and betaines. The roles of these hormones are essential to plant health. Most of these are only required in very small proportions. There are many different auxins and they all have their specific roles. Their main functions are the balanced control of speed of growth. They have both growth stimulating as well as delaying functions. They stimulate root-growth, prevent bud-forming or opening at the wrong times.
  • Seaweed can play an important role in the production of the plant’s own auxins, because the enzymes formed with the help of trace elements from the liquid seaweed fertilizer play an important role in the formation of these auxins.
  • Cytokinins are another group of important plant hormones. They initiate and activate basic growth processes. The cytokinins available in liquid seaweed extract stimulate growth with greater vigour, because they mobilise nutrients in the leaves. They also provide protection from marginal frost (to -3 C). Cytokinins also retard the senescence (aging processes) in the plant.
  • Betaines play an essential role in the osmotic processes in plants. They help to increase the water uptake in plants and are extremely helpful in dry conditions. Betaines are particularly helpful to plants under stress.
  • Liquid seaweed fertilizers, (especially the alginates in the seaweed) act as soil conditioners. The alginates react with metals in the soil and form long and cross-linked polymers in the soil. These polymers improve the crumbing in the soil, and swell up when they get wet, and retain moisture for a long period.

How is Liquid Seaweed Fertilizer Made?

Liquid seaweed fertilizers are made from various species of seaweed, which are washed, dried, milled and processed to enable the natural benefits which the seaweed provides to act immediately upon coming into contact with either the plants foliage or the soil itself. This speeds up the natural processes by converting raw seaweed into an easily applied digested weed.

Harvesting methods ensure sustainability of the natural crop, and the selection of healthy weed growing under optimum conditions and season, guarantee the best growth promoting substance yield/activity in the liquid seaweed product.

Products are produced with no acid, caustic or organic solvents. Liquid seaweed fertilizer is a truly organic product that has been extensively used in organic grower trials.

Kelp Forest

I can’t rave enough about the benefits to using a liquid seaweed fertilizer on your garden, be it on your lawns, your flower beds, your vegetables or even on your houseplants. I personally have found the results incredibly impressive, and I love the fact this is a natural product which is harvested in a way that won’t have any negative impact on the environment, or the sustainability of the seaweed itself. Those of you that have read my other articles on growing vegetables will know that I only grow my produce organically and I refuse point blank to spray any pesticides on my crops. The other advantage I have discovered is that the liquid seaweed fertilizer applied as a foliar feed actually seems to deter such nasty pests as greenfly and whitefly organically. What more could I ask for!

Seaweed as a Fertiliser – 14 reasons you should use it:

1. Balanced natural fertiliser – contains major plant nutrients and wide range of micronutrients, making it ideal for addressing deficiencies.
2. Conditions the soil- contains mannitol and alginic acid which acidifies soils and helps plants absorb nutrients.
3. Encourages root growth- auxins in seaweed stimulate growth of existing roots, particularly lawns.
4. Earlier, better, bigger crops- Betaines which are plant hormones, improve chlorophyll production, resistance to changeable weather including frost. regular foliar feeding helps growth, earlier flowering, heavier cropping and increased yields.
5. Crops store longer- regular foliar feeding with seaweed increases plant resistance to bacterial and fungal decays which can spoil stored crops.
6. Stimulates your microbes- complex carbohydrates in seaweed stimulate microscopic soil fungi and other soil microbes; this increased activity hightens the availability of the soil nutrients.
7. Improves nutritional value of crops- our soils are generally short in selenium and iodine and half our diets are short in iodine, regular applications of seaweed gets these valuable minerals into our soils and crops.
8. Produces sweeter fruit- Cytokines are natural plant growth hormones found in seaweed, they increase sugar levels in plants, resulting in robust growth and sweeter fruit.
9. Helps seeds to sprout- seaweedss retain their micronutrients, natural ammino acis and plant growth hormones, these work together to assist disease like damping off and assist seed germination
10. Reduces shock- these plant hormones lessen the impact of transplant shock.
11. Increases strike rate- Auxins in seaweed help cuttings establish
12. Reduces fruit drop- Cytokines help reduce the amount of embryonic friut aborted and stimulate early flowering
13. Fights nematodes- helps suppress nematodes (eel-worms). It reduces their breeding, weakening them so they find it harder to invade plants and contains antibiotics which helps reduce populations.
14. Improves frost tolerance- Seaweed helps strengthen cell walls, which helps reduce frost damage.

Seaweed fertiliser is a richly organic and abundant material that can be used to supplement your soils nutrition to improve your plants health. This is especially important if the soil where you live is of particularly poor quality, since seaweed can be a very inexpensive and rich way to feed your soil and make it viable for plant life.

You can find seaweed for fertiliser if you live near the coast, it is abundant, inexpensive or even free, be careful however as seaweed can contain many pollutants, in addition it will contain a high level of salt which will need to be carefully removed before applying around the garden.

If you do not live near the coast or you find all this to be too much of a hassle, you could use 100% water soluble seaweed extract, these extracts have the following benefits:

  • They have a long shelf life more than seaweed liquids
  • They do not contain a strong odour
  • They are easy to use and store
  • They are very cost effective.

Therefore if you have poor soil quality or just want to give it and your plants a boost. Water soluble seaweed extract can be great, inexpensive and convenient way to feed everything in your garden, its rich in nutrients and includes the 4 major plant hormones all living plants require. A little goes a long way as 1 gram to 1 litre of water gives the best results.

It is simple to do. Just water your plants with this nutrient rich water and watch them grow! Anytime you want to give your plants a drink, do so with water soluble seaweed extract. Youll get back what you paid for our product many times over because of the enjoyment you will recieve from your beautiful new garden, or from your produce in the vegetable patch. you will wonder what you ever did without it!

Seaweed and it’s Growth Hormones

If you’re like me, you look through catalogs every year about this time ordering supplies. You look at things like seaweed products, humic acids and so on and wonder how well they work. There are alot of ways to spend money as a farmer, and with limited capital there can only be so much experimentation.

According to my research, SEAWEED EXTRACT really does work. Although with any product you must use it correctly.

Although there are some inconsistencies most scientific studies I read (about 1 dozen and there are alot more) find SEAWEED EXTRACT does really do the things advertised. It is a worth while purchase. The use of seaweed as a growth stimulator is widely supported by scientific studies. There is evidence to support the idea thatseaweed is useful in helping plants through stress, including drought, disease and cold weather. of coarse seaweed applications cant be a substitute for managing soils properly but it can provide a boost to your plants.

Seaweed has many nutrients and is high in micronutrients such as iron, zinc, molybdenum, boron, manganese and cobalt. but what really does the job are the plant hormones it contains, which include auxins, gibberellins and cytokinins.

These hormones when applied either to the soil or the leaf as a foliar spray cause the treated plant to undergo changes of various kinds, including root stimulation, thicker and stronger stems. an increase in vegetative growth and an increase in fruit or seed yeild. The hormones seem to protect the plant in times of stress, such as disease and insects, cold weather and drought. All three hormones protect against plant aging and death by promoting functions and structural integrity of plant cells.

Cytokininsare primarily responsible for cell divisions, while gibberellins are involved with germination. auxins are produced in the growing tips of the plants and control the growth patterns including the elongation in the stem and roots.

Reccommended Rates of Use


Gardeners should soak uncut potatos sets in a 1 in 200 solution of seaweed extract for 24 hours before planting, and spray the rows with 15 litres an acre of solution just before final earthing up. Then give a further 15 litres per acre as late as possible before leaves close over the rows. Dilution should be about 1 in 5 in each case.


Spray soil and plants every 2 to 3 weeks throughout their growth stage in 1 in 100 solution.


If seedlings are pricked out from peat cubes they should first be soaked in 1 in 100 solution, the plants should then be watered with the same strength solution every 2 to 3 weeks during the growing period.

Dilution rate is 1 part Extract to 80 parts water, i.e. 25ml of the Extract should be mixed with 2 litres of water.

Crop & Plant Enhancer

Dressings: Every 3 weeks during growing season, UNDILUTED AMOUNTS: 250ml/500m2 9 fl.oz./590 sq yards

Tightly Mown Green Lawns

Dressings: Every 3 weeks during growing season, UNDILUTED AMOUNTS: 250ml/500m2 9 fl.oz./590 sq yards

Non-Mown Grass Areas

Twice Annually UNDILUTED AMOUNTS: 5-10 litres per hectare

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