Liquid seaweed with humic and fulvic acid, each at its own rate
Help your soil hold on to the feed you put down, and keep a dilute seaweed biostimulant going through the season, from one order. The trio is Brix+ liquid seaweed, humic acid granules and fulvic acid powder, each used at the rate on its own page, alongside your usual feed.
Brix+ is a liquid kelp extract, diluted and watered on or sprayed. The humic granules work in the soil and help it hold nutrients. The fulvic powder dissolves fully and carries trace elements into the plant.
What is in the trio: Humic Acid Granules, 70%: 250 g; Fulvic Acid Powder, 70%: 250 g; Brix+ Liquid Seaweed Biostimulant: 500 ml.
A note on order of use, since it is the question we get asked. The humic and fulvic acids go to the soil first: dissolve them, water them in, and they keep working between feeds. Brix+ is the one you reach for during the season, every 10–14 days as a leaf spray or every 4 weeks as a soil drench.
Seaweed extracts have a reasonable evidence base as biostimulants, and humic acid a good one for holding nutrients in the soil. None of the three replaces feeding the soil properly.
Packed in Stockport. Each product keeps its own dilution and application rate in the trio. More in Biostimulants, Seaweed Fertiliser, Humic and Fulvic Acid and Bundles & Kits.
Pick a size on the product form. Each size is a full set of the three packs below.
- Entry (250 g humic + 250 g fulvic + 500 ml Brix+): Humic Acid Granules, 250 g; Fulvic Acid Powder, 250 g; Brix+ Liquid Seaweed, 500 ml
- Mid (500 g humic + 500 g fulvic + 1 litre Brix+): Humic Acid Granules, 500 g; Fulvic Acid Powder, 500 g; Brix+ Liquid Seaweed, 1 litre
- Large (1 kg humic + 1 kg fulvic + 1 litre Brix+): Humic Acid Granules, 1 kg; Fulvic Acid Powder, 1 kg; Brix+ Liquid Seaweed, 1 litre
Rates stay on each component listing. The size picker only changes how much of each pack you get.
Each is also sold on its own: Humic Acid Granules · Fulvic Acid Powder · Liquid Seaweed Brix+
How the three sit together
- Brix+ through the season as a dilute drench or leaf spray
- Humic granules in the soil, holding nutrients between those feeds
- Fulvic powder in solution, moving nutrients
- On top of your usual NPK feed
Seaweed plus both fractions
- Brix+ for the seasonal biostimulant; humic and fulvic for the soil
- Order of use is soil first, seaweed through the months
- Three products, three dilutions
The two-jar pair
- The humic and fulvic pair if you already have a seaweed you like
- Brix+ on its own if you only want the liquid seaweed
Dr Forest packs this set in Stockport.
How the three work together
Brix+ is an Ascophyllum nodosum kelp biostimulant with a deliberately low NPK (N 0.26%, K 1.65%). Reviews of seaweed extracts treat them as biostimulants of growth and stress tolerance, so keep feeding the plant as usual (Khan et al., 2009; Craigie, 2011). The humic granules work in the soil, where humic substances add cation exchange capacity and help hold nutrients; fulvic acid is the small, soluble fraction that moves into the plant and carries trace elements with it (Canellas et al., 2015). For the longer version, read What is seaweed fertiliser?.
How to use Humic, Fulvic & Seaweed Trio
Water the humic and fulvic in at the rates below. Use Brix+ through the growing months, every 10–14 days as a leaf spray or every 4 weeks as a drench.
There is no combined ml-per-litre for the set. None of the three replaces a fertiliser.
Rates from each product page
| Product | Rate | How often |
|---|---|---|
| Brix+ liquid seaweed | Foliar spray, all plants: 2–2.5 ml per litre of water. Soil drench, all plants: 5–12.5 ml per litre of water | Foliar: every 10–14 days or as required. Drench: every 4 weeks |
| Humic Acid Granules | Soil drench, general vegetable garden and allotment: 0.5 g granules per litre (≈350 mg/L humic acid), 500 ml–1 L per medium plant | Every 3–4 weeks |
| Fulvic Acid Powder | Foliar: 0.5 to 1 g per litre. Soil drench: 0.5 to 1 g per litre, watered on at about 5 litres per m². Stop at 5 g per m² for the whole season | Foliar: every 2 to 4 weeks while plants are growing |
Mixing in one can? Jar-test first: mix a small amount of each at its working dilution in a clear jar and check for curdling or sediment. Brix+ is mildly acidic and should not go into low-pH solutions, and hard tap water uses up the fulvic, so use rainwater where you can.
Humic stains. The solution stains porous surfaces: paving, concrete, grout, light-coloured clothing, and timber. Work over soil or grass. Rinse spills on hard surfaces immediately.
Brix+ can mark fruit. Avoid spraying close to harvest on produce prone to staining, as the brown liquid can mark pale-skinned fruit.
Brix+ in the cold. Below 5°C it may crystallise or throw a sediment; that is normal, and warming it gently and shaking brings it back.
- Dissolve the humic granules in water with stirring. For the fulvic, shake each gram in about 30 ml of warm water in a jar for 30 to 60 seconds, then dilute. Water both in.
- Use Brix+ as a dilute leaf spray or drench at the rate in the table.
- Keep the NPK programme you already have.
Want a foliar amino as well? Humic, Fulvic, Seaweed & Amino Acid Set. Just the two fractions: Humic & Fulvic Acid Pair.
Humic, Fulvic & Seaweed Trio: questions
It is a biostimulant set. Brix+ is a liquid seaweed with a deliberately low NPK (N 0.26%), and the humic and fulvic acids work alongside your usual feed.
Humic and fulvic watered into the soil first; Brix+ through the season. The rates are in the How to Use table.
Brix+ and fulvic have foliar routes on their pages. Humic is soil-first. Follow those pages.
No. Brix+ is deliberately low NPK, so keep your usual feed.
Both. Brix+ is an extract of the kelp Ascophyllum nodosum, and the humic granules are extracted from leonardite. The fulvic powder is produced by enzymatic hydrolysis to 70% fulvic acid.
All three are natural materials: kelp extract, leonardite humate and fulvic acid. We do not call the set certified organic.
In Stockport, by Dr Forest.
Yes. Wash produce as usual, and stop spraying Brix+ a few days before you pick pale-skinned fruit.
Often, yes. Jar-test first: mix a small amount of each at its working dilution in a clear jar and check for curdling or sediment before you fill a sprayer or can. Brix+ is mildly acidic and should not go into low-pH solutions, and hard tap water uses up the fulvic, so use rainwater where you can. Use each one at the rate on its own page. The humic acid is mainly for the soil; Brix+ and fulvic also have foliar uses.
Yes. At today's prices (October 2026) every size costs about 12% less than buying the same products separately. The smallest size is £29.95 against £33.97 bought one by one, a saving of £4.02.
Not in the bundle. The sizes are fixed: 250 g humic + 250 g fulvic + 500 ml Brix+; 500 g humic + 500 g fulvic + 1 litre Brix+; 1 kg humic + 1 kg fulvic + 1 litre Brix+. If you want different amounts, buy the products on their own pages and mix the sizes as you like.
Yes. Each one is sold on its own: Liquid Seaweed, Humic Acid Granules, Fulvic Acid Powder.