Struggling to craft the thriving garden you first dreamed of when you invested in equipment, seeds and plenty of Sunday mornings?

While a certain amount of green fingers might come into it, it might also be the quality of your soil that's preventing your success. But don't think it's time to give up and wave goodbye to your green dreams: a dash of liquid seaweed might just be the missing piece in the horticultural puzzle.

Liquid seaweed is a natural fertiliser made from seaweed that's used to enhance plant growth and health. Ideal for all kinds of plants, flowers, fruits and vegetables, this potent fertiliser is renowned for its ability to perk up your garden like never before.

Unlike traditional soil which may contain questionable ratios of nutrients depending on where you live, liquid seaweed comes bolstered with all of the good stuff that your plants need to succeed. Those nutrients include things like nitrogen, potassium, phosphorus, magnesium and calcium, as well as trace elements like iron, zinc, and copper.

Didn't think your plants needed their own five-a-day to survive? Think again.

What does liquid seaweed do?

When liquid seaweed is applied to your plants, it can help stimulate to root growth, improve plant health, increase its resistance to pests and diseases and generally boost your overall plant growth and yield. The natural hormones present in seaweed can even help plants to better withstand stress from environmental factors like drought, heat and cold. Perfect if you're gardening in the UK and preparing for those famous lows of -12oC and those highs of 40oC.

It's easy to add into your gardening routine, too: just mix your liquid seaweed with water according to the instructions on the label, then apply the mixture to the soil around the base of the plant.

We've rounded up all of the best liquid seaweed fertilisers.

Doff Liquid Seaweed Concentrate 1L

Doff’s Liquid Seaweed Concentrate is a highly efficient plant food manufactured by one of the largest horticulture brands around. So, if you’re looking to stick with a tried and tested winner, this is an option that never fails to deliver.

Made from high-quality seaweed and with an entirely natural composition, this fertiliser is both safe and eco-friendly. This plant food is suitable for use in all seasons and is ideal for vegetables, fruits, flowers and shrubs. It contains essential plant nutrients like nitrogen, phosphorus, potassium and trace elements that are quickly absorbed.

Buy now £4.00, Wilko

MULTI MITE Organic Liquid Seaweed Concentrate - Cold Press

Thought cold press was just reserved for juices? Think again. MULTI MITE’s Organic Liquid Seaweed Concentrate is a versatile product that can be used on a wide range of plants, including ornamental plants, vegetables, fruits and herbs.

Best for those who only want the best of the best fertilisers around, it’s processed using a cold-press method that retains the maximum amount of beneficial compounds, like plant growth regulators, amino acids, trace elements and vitamins.

Buy now £18.45, Amazon

Wilko Seaweed Plant Tonic Liquid 1L

Cheering your plants up doesn’t have to cost a fortune, as proven by Wilko’s own-brand liquid seaweed. This plant tonic is made with concentrated seaweed extract and offers a highly effective solution to encourage faster and healthier plant growth without setting you back a fortune.

Each pack contains a handful of nutrients and minerals that are essential for healthy plant growth, including potassium, magnesium and nitrogen. Just add the recommended amount to water and apply as directed and wait for the results to come.

Buy now £0.30, Wilko

Sea-Chem Premium Organic Liquid Seaweed

Sea-Chem’s Premium Organic Liquid Seaweed is a highly effective fertiliser that’s derived from a range of sustainably sourced marine plants. It’s entirely organic and eco-friendly, so it makes a great option for improving your plant’s resilience, root growth and its overall health - while also enhancing the taste, yield and quality of crops. Carefully refined over a period of ten years, this is a premium organic fertiliser for discerning growers.

Buy now £13.49, Sea-Chem

Angus Super Lawn Organic 30% Liquid Seaweed

Angus’ Super Lawn Organic 30% Liquid Seaweed has a unique formulation that provides the perfect balance of minerals, trace elements and vitamins to promote robust growth and health for the full year-round.

It might be a little pricier than other liquid seaweeds but with that price comes a higher concentration of all the good stuff. Derived from fresh organic seaweed, it’s safe for both the environment and the garden’s health and it also contains natural growth hormones that improve root development and reduce plant stress levels.

Buy now £21.99, Green-care

Hydra SeaGrow - Organic Seaweed Extract Concentrate Plant Fertilizer

You’ll find Hydra SeaGrow’s Organic Seaweed Extract Concentrate Plant Fertiliser in a range of different bottle sizes, which means it’s easy to choose one that suits the size of your garden without wasting any or realising halfway through that you maybe should have bought two.

What makes Hydra SeaGrow stand apart from other fertilisers is its natural and sustainable approach to plant nutrition: it contains no harmful chemicals, which promotes healthier soil and crops, leading to better plant yield and quality.

Buy now £10.99, Amazon

MARPHYL Plant Food Fertiliser

One of the most popular liquid seaweed brands around, MARPHYL’s Plant Food Fertiliser is made from concentrated marine phytoplankton and contains everything you need to prove that the grass can also be greener on this side. MARPHYL helps to improve soil health, increase plant growth rates and enhance overall plant health and vitality while maintaining its all natural and organic approach to fertiliser.

Buy now £11.90, Amazon

Maxicrop XNATF61L All Purpose Organic Garden Natural Fertiliser

It might not have the catchiest name around but Maxicrop’s XNATF61L All Purpose Organic Garden Natural Fertiliser is jam-packed with essential nutrients like nitrogen, potassium and phosphorus which, together, promise to zhuzh up your plants like never before.

While this fertiliser isn’t entirely liquid seaweed, it does come with seaweed extract, making it a great introduction to elevating your fertiliser without making too large of a change all at once.

Buy now £8.99, Amazon

Westland Seaweed Enhanced

Westland Seaweed Enhanced is made up of a unique blend of seaweed extracts and other natural ingredients and offers a versatile way of improving your plants’ health quickly and easily.

A premium quality fertiliser that’s specifically crafted to enhance the growth of plants both indoors and outdoors, this is one you don’t have to worry about supplementing with another product: use it on as many of your plants as needed.

Buy now £9.00, Wilko

Florasoul Plant Booster Vegan Organic Fertilizer

If your plants happen to follow a vegan diet too, you’ll probably want a fertiliser that subscribes to the same approach. Florasoul’s Plant Booster Vegan Organic Fertilizer is a concentrated formula designed to not only boost plant growth but also to enhance flowering.

Vegan, organic and free from any harmful chemicals that can harm the environment, this is one of the safest liquid seaweed fertilisers around and penetrates deep into the soil, allowing plants to absorb nutrients effectively.

Buy now £10.27, Amazon


It's budget-friendly, it does the job and it's multi-purpose: if you choose one liquid seaweed, go for Doff Liquid Seaweed Concentrate.

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