Humic and Fulvic Acid

Humic and fulvic acid: two fractions, two jobs

Our humic products come from leonardite, an oxidised form of soft brown coal laid down from ancient plants. Our fulvic powder is made differently, by enzymatic hydrolysis rather than mining. What separates the two fractions is size and how they behave in water.

Humic acid is the larger fraction. It stays put in the soil, clings to clay and organic matter, and gives thin or sandy ground a few more places to hold calcium, potassium and magnesium rather than losing them to the next downpour. At garden rates it is a nudge, not a revolution, and its effects are judged in seasons.

Fulvic acid is the smaller fraction. It stays dissolved at any pH, binds trace minerals such as iron, zinc and manganese, and is small enough to carry them with water to the root — and, to some extent, into a sprayed leaf. It shows its hand in weeks rather than years.

Humic for the soil, fulvic for the plant: that is the short version. The longer answer, including which to pick if you only buy one, is in Humic vs fulvic acid: the difference, and which you need.

Choosing a format

Pick by where you want the acid to work.

• Humic in a watering can or drip line: Humic Acid Flakes
• Humic in the ground for months: Slow Release Humic Acid
• Plant-side help, sprayed or watered on: Fulvic Acid Powder
• Both soluble fractions in one order: Humic & Fulvic Acid Pair

For the can: Humic Acid Flakes

Humic Acid Flakes are 70% humic acid and fully water-soluble. Weigh them into a can and they dissolve within minutes to a very dark brown with no sediment. That makes them the format for drenches, transplanting, compost tea and drip lines. Anyone who has brewed humate tea from a part-soluble product and found sludge in the can and grit in the nozzle will see why full solubility matters. A drench does its work over days and weeks and is largely used up, so you repeat it through the season.

For the ground itself: Slow Release Humic Acid

Slow Release Humic Acid is the same leonardite humate at 70% humic acid, but pressed into 2–4 mm granules that are made not to dissolve. They will not go through a sprayer — rake them into a new bed or a seedbed before turf, or mix them through compost at potting, and soil life works on them over months. This is the format for ground you are improving over years: an allotment plot, a hungry sandy border, a new lawn on thin topsoil.

For leaf and root: Fulvic Acid Powder

Fulvic Acid Powder is 70% fulvic and 99% soluble in cold water, so it goes on as a foliar spray or a drench without sediment. Two habits help. Weigh it: rates are in grams per litre, and past a certain point the benefit goes backwards. And use rainwater if you have a water butt — the calcium in hard tap water ties up some of the fulvic before it reaches a leaf.

Search "fulvic" online and you will find everything from detox drinks to products that are not fulvic acid at all. Ours is a garden input for soil and plants, not for eating or drinking.

When you want both

Plenty of gardeners who start with one acid end up wanting the other, which is why we sell them as a pair. The Humic & Fulvic Acid Pair is Humic Acid Flakes and Fulvic Acid Powder in one order — 250 g, 500 g or 1 kg of each. Both are for dissolving; the pair does not include the slow-release granules. If you also want soil-building that lasts the season, add a bag of Slow Release Humic Acid in spring and let the pair do the in-season work from the can.

Two sets go further:

• Seaweed, Humic & Fulvic Trio adds Brix+, our kelp-based liquid seaweed, to the flakes and powder. Seaweed is the tonic most gardeners reach for first; the humic and fulvic help the soil and roots make more of your feed.
• Humic, Fulvic, Seaweed & Amino Set is the foliar feed set: the same three plus Organic Amino Acid Fertiliser powder, all soluble, for spraying when growth is fast or a cold spring soil has the roots working slowly. A foliar spray does not replace feeding the soil, and we would not pretend it does.

Each part keeps its own rate on its own listing. If the seaweed or the aminos are what interest you, the wider biostimulants range is the next shelf along.

What they will not do

Neither acid is a fertiliser. They carry little or no nitrogen, phosphate or potash, so they go beside a proper feed and never instead of one. On empty soil, humic and fulvic will only help a plant make better use of not very much. Start with compost and a real feed from our organic fertilisers, or bulk up thin ground from the soil improvers, then add these on top.

They will not drain a waterlogged bed, and at pack rates they will not shift your pH in any way that matters. Humic matter does help a soil resist sudden swings — that is genuine buffering — but a single pack adds little to what the soil already holds. If you need to move your pH, that is a job for lime or sulphur. On chalk, a fulvic spray can help a pale plant use the iron that is already there, but the chalk stays chalk, and a badly yellowed plant needs sequestered iron. Doubling the fulvic rate "to be sure" is the commonest mistake we hear about.

The results are real but quiet: a better root, a greener leaf, a soil that holds water a little longer in August. Anyone promising a transformation in a fortnight deserves suspicion, us included.

Rates and method

Pack rates sit on each product page. For the full method, crop by crop, read how to apply humic acid and how to apply fulvic acid. The published trials those guides draw on tested a range of humic and fulvic products, not ours in particular.

The flakes and fulvic powder are weighed and packed here in Stockport, with the percentage on the front of the pack. Garden use only: soil, pots, lawns and leaves. Store sealed and dry, out of reach of children and pets.

Common questions