A Natural Ally for Plants
For thousands of years, coastal communities have turned to seaweed to nourish the land. Today, modern science backs what tradition has long known: seaweed is one of the most effective and sustainable fertilisers available. It’s not just about feeding plants—it’s about building healthier soil, improving resilience, and working in harmony with nature.
Whether you're caring for houseplants, feeding a vegetable garden, or maintaining a lush lawn, seaweed fertiliser offers a gentle but powerful solution.
What Makes Seaweed So Effective?
Seaweed is packed with naturally occurring nutrients and compounds that support plant health from the roots up:
- Over 60 trace minerals including potassium, calcium, magnesium and iron
- Natural plant hormones (cytokinins, auxins, gibberellins) to encourage root and shoot growth
- Alginates and polysaccharides that improve soil texture and water retention
- Antioxidants and stress-reducing compounds that help plants cope with drought, pests and disease
These nutrients are delivered in a form that plants can absorb easily, making seaweed especially effective when used as a liquid fertiliser.
Science-Backed Results
Recent studies in the UK and globally have shown:
- Seaweed fertilisers can improve root growth by over 40% compared to untreated plants
- Regular applications lead to stronger, greener leaves and improved flowering
- Soil treated with seaweed supports better microbial life, aiding long-term fertility
- Lawns and crops showed increased resistance to common fungal diseases and extreme weather
Seaweed isn’t just a fertiliser—it’s a natural biostimulant that supports healthy, balanced growth.
Where Seaweed Fertiliser Works Best
Houseplants
Seaweed feed provides a gentle tonic for houseplants, boosting leaf health and root strength without overwhelming them. Ideal for monthly watering or recovery after repotting.
Vegetable Gardens
Seaweed supports nutrient uptake and builds natural plant immunity, helping crops thrive without chemical boosters. It's especially effective during transplanting and flowering stages.
Lawns
Applied to lawns, seaweed encourages stronger roots, improved drought tolerance, and a greener appearance. It supports soil life and helps grass bounce back after mowing or dry spells.
Flower Beds, Shrubs & Trees
Seaweed fertiliser helps perennials and woody plants develop stronger root systems and more vibrant blooms. It also improves soil structure around established plants.
Sustainable by Nature
Unlike synthetic fertilisers, seaweed is renewable and low-impact. It grows quickly, requires no farmland or freshwater, and helps absorb carbon from the atmosphere.
At Aquaculture, we go a step further by using only waste or naturally cast seaweed from Cornish shores—hand-harvested with zero damage to live marine ecosystems. It’s a fully circular, regenerative approach that supports both soil and sea.
In Summary
Seaweed fertiliser is a simple, time-tested, and science-backed way to improve plant health and soil vitality. From houseplants and veg beds to lawns and trees, it offers wide-ranging benefits in a natural, sustainable form.
To explore the benefits at home, try Aquaculture’s liquid seaweed fertiliser—made in Cornwall using 100% repurposed seaweed.
