• Seaweed


Put down the synthetic fertilisers and embrace natural growing instead—your soil life will thank you for it! Begin by adding seaweed to your garden or grow room. This natural biostimulant contains a wealth of nutrients, including a long list of minerals and vitamins, that bring plant health and vitality to new highs.
(6) Write a review
On sale!
Reduced price!

£14.31 (-0%)

Add to Saved Items

  • More info
  • Questions (0)
  • Reviews (6)

Seaweed: A Tonic for Weed Plants

Although seaweed grows in a very different environment from cannabis plants, it still plays an integral role in natural gardening practices. These aquatic plants are loaded with key minerals and vitamins that help cannabis plants thrive. Seaweed takes average, run-of-the-mill plants and turns them into flourishing specimens that live up to their ultimate genetic destiny—thick, resinous buds and all.

Seaweed & Kelp: Powerful nutrients for your cannabis plants

Our seaweed product harnesses the power of three seaweed species, one of which autumns under the category of kelp. But why use seaweed and kelp for cannabis? Home growers and large-scale organic agricultural operations use them as biostimulants to protect plants against stress, improve crop quality, and enhance nutrition efficiency. Unlike synthetic fertilisers, seaweed doesn’t contain salt-based nutrients that can damage beneficial microorganisms and disrupt nutrient cycling in the soil. Instead, it serves as a source of food within the soil food web; microbes gradually break it down and release plant-available compounds. In the flowering stage, kelp also delivers nutrients that enable plants to form bulbous buds coated with trichomes and cannabinoid-containing resin.


Apply 1 gram per litre of soil indoors and 1.5 grams per litre for soil recovery.

RQS Seaweed: A Detailed Look

So, what does administering seaweed provide for your weed plants? Over time, your specimens will receive a banquet of nutrients that fulfil key physiological functions, including:

Total nitrogen (N) 5%
Phosphorous (P205) >1%
Alginates 7.8%
Magnesium (MgO) 2%
Potassium (K) 6%
Iron (Fe) 0.96%
Vitamins A, B1, B2, B12, C, D, E, K
Organic matter <55%
Types of seaweed
Ascophyllum sp.
Sargassum sp.
Macrocystis sp.

RQS Nutrients: The Best
Fertilisers for Cannabis

Easy Roots Rhizobacter
Easy Roots Trichoderma
Easy Roots Mycorrhiza Mix
Bat Guano
Easy Boost Organic Nutrition
Easy Grow Booster Tablets
Easy Bloom Booster Tablets
Easy Combo Booster Pack
Easy Plus Micronutrients
Thicker Flowers
Bigger Flowers
Sweeter Flowers
Incompatible (unless used in separate phases of growth) High in phosphorous (check Special considerations for each product)

    By N. J. on 15/Feb/2024 :

    Title : Cultiver respectueusement
    Comment : Très bon rapport qualité prix, que du bonheur pour nos bébés.

    By M. H. on 17/Oct/2023 :

    Title : Seaweed
    Comment : I’ve just purchased this product and I’m very excited to use this when I start my next grow I’ve read all the reviews and I must say I’m very impressed I’ve been using royal queen seeds for years but decided to join the family permanently so I’ve ordered all the nutrients from royal queen seeds and can’t wait to see my babies florist I never use any other products again and less it’s royal queen seeds 👍

    By D. P. on 11/Aug/2023 :

    Title : really good! enough for a very long time!
    Comment : Very good Product!! My plants looked a bit sad till it came in the mail. After the first application as a tea / foliar spray which was bubbling for 24h, my plants started praying untill this moment and it seems like they grow much faster! This is worth full 5 Stars. Especially when growing materials are on sale the price is unbeatable. Thats also when i grabbed one to test and it came in very handy! Great price / performance. Thanks RQS! I will sure buy it again when the bag is nearly empty. :)

    By G. E. on 26/Jun/2023 :

    Title : ******
    Comment : Davvero un prodotto TOP a 6 stelle GTA

    By B. Z. on 20/Mar/2023 :

    Title : Bilbo B.
    Comment : One of the must have products for organic farming! Thanks RQS and Team

    By P. R. on 02/Mar/2023 :

    Title : Master P
    Comment : Moin, danke RQS für dieses erstklassische natürliche Düngungsergänzungadditive. Einfach mit ins Substrat geben. Vorsicht bei der Dosierung gerade in der Growphase, später in der Blütephase zeigt sich die geballte Algenpower. Danke RQS für dieses ergiebige Produkt in perfektem Preis-Leistungs-Verhältnis

    You cannot post a review because you have not purchased this product

No customer questions for the moment.

Only registered user can ask a question. Login
Recommended products:
Customers who bought this products also bought:

Are you aged 18 or over?

The content on RoyalQueenSeeds.com is only suitable for adults and is reserved for those of legal age.

Ensure you are aware of the laws of your country.

By clicking ENTER, you confirm
you are
18 years or older