Flourish - Concentrated Seaweed Extract Plant Food

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The Power of Purity

Brimming with bioactive compounds and phytohormones, flourish reduces stress, improves plant growth, and unleashes bloom potential. Boost germination rates, enhance vegetative vigour, and witness stunning flower development.

  • 100% Natural and Organic Approved Biostimulant
  • Extra-Refined: Remains Stable in Reservoir for Weeks
  • Reservoir Ready: Compatible with Soil, Coco, and Hydro
  • Keeps Your Plants Thriving by Increasing Stress Tolerance
  • Enhances Germination Rates
  • Boosts Vegetative Vigour
  • Improves Flower Development
  • Root feed or Foliar Spray

Delivering Biological Benefits to All Growers

The bioactive compounds in seaweed extracts offer plants myriad benefits such as increased nutrient uptake, elevated environmental stress tolerance, protection from pathogens, improved growth response, and enhanced fruit and flower development. Contrary to popular belief, pure seaweed extracts are not fertilisers because they actually contain very low quantities of nitrogen, phosphorus, and potassium. Seaweed is often misreported as a good source of trace elements. However, it's the bioactive compounds in seaweed that are responsible for its growth-enhancing effects.

Key bioactive compounds include:


These plant hormones coordinate cellular activities, leading to improved growth characteristics like increased shoot and root growth, flower numbers, fruit and bud set, increased chlorophyll content, and yield increase. Cytokinins, auxins, and gibberellins are some of the major phytohormone components in seaweed extracts.


These compounds in seaweed extracts can enhance plant resistance to a wide range of stressors, including biotic factors like pests and disease. Alginic acid, a polysaccharide found in seaweed, can induce changes in gene regulation with key implications for plant defence mechanisms. Other polysaccharides found in seaweed include laminarin, fucoidan, and mannitol.


Found in seaweed, these modified amino acids help protect the plant against environmental stresses such as drought, salinity, heat, and cold stress.

How to Use flourish

Unlike traditional seaweed extracts, flourish is clean and pure enough for use in all growing situations, from organic living soil to hydroponic reservoirs. Through our proprietary processing technique, we've created a unique, ultra-purified extract. Experience a clean, fully soluble, and highly stable seaweed extract that remains fresh in your hydroponic system for weeks - no fouling, no blockages, just steady support for your plants—even in the most demanding growing conditions.

Root Feed

Apply 0.25-0.5ml per litre with every watering.

Can be applied as a stand-alone feed or mixed with other nutrients and additives as part of your regular nutrient program. It is tank stable and highly compatible with other products.

Foliar Feed

Spray 10ml per litre every 10-14 days.

Works excellently as a foliar spray, particularly during key growth stages such as on new clones to promote roots, at transplant to avoid shock, during transitional growth stages between vegetative and fruiting/flower, and to protect from environmental stress. Spray on a regular 10-14 day regime.

As a root feed, flourish is suitable for use in all growth stages. It works great as a seed soak, cube soak, and all-round propagation aid, providing young plants and seedlings with a bioactive boost when they need it most. Continue to use flourish when transplanting into a fresh substrate to help your plants cope with transplant shock and encourage explosive root growth. Once you have repotted, continue using flourish throughout the vegetative and flowering growth phases. You can stop using flourish as a root feed one or two weeks before harvest.

As a foliar feed, flourish can be used throughout propagation and vegetative growth. If you're growing fruiting plants, flourish can be sprayed throughout the cycle right up to harvest. For flowering plants, stop foliar sprays once the flowers have started to form.

Ideal for High Intensity Cultivation Environments

Growing with LEDs? flourish is your go-to solution to overcome the challenges of higher air temperatures, faster wet/dry cycles, and intense LED lighting. Thrive through every growth stage, from seedling to harvest, and enjoy a garden that truly wins, not just making it to the finish line.

flourish can be used throughout the plant’s lifecycle, it delivers a natural boost from seedling or cutting, right through to harvest. Whether you’re growing in living soil, rockwool or deep-water culture, flourish helps your plants to focus on thriving, not just surviving.

Sourced from Pristine Waters

flourish is derived from the renowned seaweed species, Ascophyllum nodosum, hand-harvested from the clean tidal waters of Northwest Scotland and the West Coast of Ireland. Our commitment to sustainability means that every batch is extracted without harmful chemicals, ensuring the highest quality bioactive compounds that nature intended.

Seaweed vs Seaweed Extracts

Throughout history, seaweed has been an essential ally to farmers and growers. Its incorporation as dried seaweed meal into the soil or growing media yields numerous benefits, such as enhancing soil microbial activity, elevating potassium levels, enriching organic matter, and improving water retention. However, this traditional approach may take longer to yield growth-enhancing results.

Yet, it's essential to be mindful of seaweed's salt content when adding it to your soil. At Ecothrive, we conduct rigorous tests on every seaweed batch we receive, typically containing 2-5% sodium, ensuring that potential issues are skillfully sidestepped.

While seaweed incorporation in the soil has its merits, achieving robust growth responses often necessitates the addition of significant quantities, resulting in not only higher application cost but also disruption to soil fertility. That's why, since the 1950s, a more preferred and efficient method involves employing concentrated seaweed extracts as a foliar spray or through drip irrigation. This approach elicits rapid but long-lasting plant responses.

A Superior Seaweed Extract

The extraction method plays a crucial role in the quality of seaweed extracts, determining the abundance of bioactive compounds harvested. Most commonly, the aggressive liquid potassium hydroxide is used in the extraction process, leading to an alkaline mush of seaweed, later filtered to produce the extract. These conventional extracts are high in potassium, which can disrupt water pH once diluted, and often lack the desired compounds for optimal plant stimulation.

Here's where flourish stands apart. Our innovative approach involves maintaining low temperature and high pressure during extraction, effectively squeezing the goodness out of the seaweed biomass. This results in a rich, wide-spectrum extract teeming with phytohormones and bioactive compounds, all achieved without any chemicals. As a final step, we meticulously remove any remaining solids from the extract. Unlike most seaweed extracts available today, flourish undergoes advanced filtration, ensuring that no residual solids disrupt your irrigation systems, spoil reservoirs, or leave unwanted residues on your precious plants' leaves.

We have created the industry’s most stable and fully soluble seaweed extract, complete with a perfectly balanced pH. This means that you can add flourish to your water or nutrient mixes without worrying about compatibility issues. Whether for foliar applications, hydro systems, organic soil, or coco coir, flourish is the ultimate natural plant biostimulant and stress-reliever.

Typical Analysis

Nitrogen 0 %
Phosphorus 0 %
Potassium 0.5 %
Sodium 0.13 %
Calcium 600 mg/kg (ppm)
Magnesium 325 mg/kg (ppm)
Sulphur 750 mg/kg (ppm)
Boron 11.5 mg/kg (ppm)
Copper 3 mg/kg (ppm)
Zinc 0.1 mg/kg (ppm)
Iron 4.5 mg/kg (ppm)
Manganese 2.5 mg/kg (ppm)
Molybdenum 0.1 mg/kg (ppm)
Bioactive compounds
Alginic Acid 4.125 g/100ml
Laminarin 1.12 g/100ml
Fucoidan 1.19 g/100ml
Mannitol 0.44 g/100ml
Betaines 36 mg/100ml
Auxins 10 mg/100ml
Gibberellins 5 mg/100ml
Cytokinin’s 10 mg/100ml
Heavy Metals
Arsenic 1.55 mg/kg (ppm)
Cadmium <0.1 mg/kg (ppm)
Chromium <0.1 mg/kg (ppm)
Lead <0.2 mg/kg (ppm)
Mercury 0.95 mg/kg (ppm)
Nickel 0.06 mg/kg (ppm)
Other Parameters
Seaweed Solids 3-4% w/v
Organic matter 2.5 %
pH 4.2

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