• Organic Malted Barley — pile of pale-gold cracked malted barley grains
  • Organic Malted Barley — 750g kraft bag with dr forest Diastatic Malted Barley label, Min 250 Diastatic Power
  • Organic Malted Barley — back of kraft pouch with Directions for Use panel
1 3

Dr Forest

Organic Malted Barley

£10.99
£10.99
Sale Sold out
Shipping calculated at checkout.
Size
  • ✓Free UK delivery on orders over £40
  • ✓Handcrafted and dispatched from Stockport
  • ✓Made with organic ingredients
  • ✓No-quibble returns

Dr Forest customers rate us 4.96/5 · 3,543+ reviews & ratings across Shopify, Amazon, Google, Trustpilot and eBay

 

High DP malted barley — enzyme-rich soil amendment that accelerates nutrient cycling, root growth & microbial activity

Diastatic Power 250+ 8 Active Enzymes Accelerates Nutrient Cycling Coarsely Crushed German Produced Organic

Every organic amendment you add to your soil — compost, worm castings, seaweed, neem, fertiliser granules — must be broken down by enzymes before plants can absorb it. These enzymes are normally produced by soil micro-organisms, but the process takes time. Malted barley short-circuits this waiting period by flooding the soil with a pre-made suite of powerful enzymes that immediately begin breaking down organic matter into plant-available nutrients. It is not a fertiliser. It is an enzyme catalyst that makes everything else in your soil work faster.

This is not ordinary malted barley. It is a high diastatic power (DP) malt produced in Germany with a minimum diastatic power of 250 Windisch-Kolbach — over 75% higher enzyme activity than standard diastatic malted barley. "Diastatic" means the enzymes are alive and active — they were not killed by excessive heat during kilning. The malting process germinates the barley grain to the exact point of maximum enzyme production, then gently dries it to preserve those enzymes intact. The result is a concentrated package of at least eight active enzyme types, each one a catalyst for a different step in the nutrient cycling process.

Coarsely crushed for ease of application as a top dressing or soil mix ingredient. The crushed form exposes the enzyme-rich interior of the grain while retaining enough structure for even distribution across the soil surface.

250+Diastatic Power (WK)
75%More Than Standard Malt
8+Active Enzyme Types
CatalystSpeeds Nutrient Cycling

What malted barley does in the soil

  • Accelerates the breakdown of organic amendments into plant-available nutrients — the enzyme suite hydrolyses proteins, starches, cellulose, chitin, and phosphate compounds in the soil, converting them from locked-up organic forms into nutrients that roots can absorb; this is the single most important function
  • Speeds up nutrient cycling after applying organic fertilisers — when you top dress with a Dr Forest granular fertiliser, the nutrients are bound in organic molecules; the enzymes from malted barley catalyse the breakdown of those molecules, making the nutrients available to plants faster than microbial activity alone
  • Feeds and multiplies soil micro-organisms — the sugars, starches, and proteins released from the grain are a rich carbon and nitrogen food source for beneficial bacteria and fungi; the enzymes simultaneously make existing organic matter in the soil more accessible to these organisms
  • Stimulates root growth and establishment after transplanting — the combination of enzyme-driven nutrient release and microbial stimulation creates ideal conditions for rapid root colonisation; growers consistently report faster establishment when barley is applied at transplant
  • Activates the chitinase-salicylic acid defence pathway — chitinase enzyme in malted barley breaks down chitin (found in insect exoskeletons and fungal cell walls), triggering systemic acquired resistance (SAR) in plants — a broad-spectrum immune priming that increases resistance to pests and diseases
  • Accelerates vermicomposting and composting — added to worm bins and compost heaps, the enzymes dramatically speed up the conversion of organic waste into finished compost; worm reproduction and activity increase measurably
  • Improves stem strength and plant structure in late flowering — growers using regular malted barley applications report increased tensile strength and reduced need for staking in the later stages of growth and fruiting

Why diastatic power matters — not all malted barley is the same

High DP Malted Barley (this product — DP 250+)

  • Diastatic power of 250+ Windisch-Kolbach — over 75% more enzyme activity than standard malt
  • Gently kilned at low temperature to preserve all enzymes intact and active
  • Contains the full suite of at least 8 active enzyme types (amylase, protease, phosphatase, chitinase, urease, cellulase, β-glucosidase, arylsulfatase)
  • German-produced to exacting brewing-industry malting standards
  • The higher the DP number, the more enzyme activity per gram — and the faster the nutrient cycling effect in the soil

Standard or Low-DP Malted Barley

  • Typical DP of 100–140 Windisch-Kolbach — significantly lower enzyme activity
  • Some malts are toasted, roasted, or caramelised for flavour — this kills the enzymes that gardeners need
  • Non-diastatic malt (e.g. malt extract, dark crystal malt) contains zero active enzymes — useless as a soil amendment
  • Food-grade and brewing-grade barley may contain residual glyphosate from pre-harvest desiccation
  • Always check for "diastatic" and a DP rating before purchasing malt for garden use

The enzyme science: how eight catalysts in malted barley accelerate every stage of nutrient cycling

What enzymes are and why they matter in organic soil

An enzyme is a biological catalyst — a protein that dramatically speeds up a specific chemical reaction without being consumed in the process. A single enzyme molecule can catalyse the same reaction thousands of times per second. In soil, enzymes are the machinery that converts organic matter (dead plant material, compost, worm castings, fertiliser granules) into the simple mineral ions (ammonium, phosphate, potassium, sulphate, sugars, amino acids) that plant roots can actually absorb.

Without enzymes, organic matter would decompose so slowly that plants would starve waiting for nutrients. Soil micro-organisms produce enzymes as they digest organic matter — this is the normal engine of nutrient cycling. Malted barley provides a concentrated, pre-made supply of these same enzymes, immediately available the moment the grain contacts moist soil. The effect is to accelerate every stage of the nutrient cycling process simultaneously — starch hydrolysis, protein breakdown, phosphate liberation, cellulose decomposition, chitin degradation, and urea conversion all running faster at the same time. No other single amendment provides this breadth of enzymatic activity.

The eight-enzyme suite — what each one does

01

Amylase — starch breakdown

Catalyses the hydrolysis of starch into simple sugars (glucose, maltose). In soil, this converts the starch content of organic amendments, root exudates, and decomposing plant material into immediately available carbon and energy for soil micro-organisms. The sudden availability of simple sugars triggers a rapid bloom of beneficial bacteria and fungi — amplifying the biological activity that drives all other nutrient cycling processes.

02

Protease — protein breakdown

Cleaves proteins into peptides and amino acids through hydrolysis. Proteins are the primary storage form of organic nitrogen in soil, compost, and organic fertilisers. Protease releases this nitrogen as amino acids and ultimately ammonium — the form that plant roots absorb. Faster protein breakdown means faster nitrogen availability. This is why growers report that organic fertilisers applied alongside malted barley produce visible results sooner than fertiliser alone.

03

Phosphatase — phosphorus liberation

Catalyses the hydrolysis of organic phosphate compounds, releasing plant-available phosphate (PO₄³⁻). Phosphorus is the nutrient most commonly locked up in organic forms that plants cannot access. Over 80% of soil phosphorus exists in organic compounds that require enzymatic breakdown before plant roots can absorb it. Phosphatase from malted barley accelerates this conversion — making phosphorus-rich amendments (bone meal, rock phosphate, compost) release their phosphorus faster.

04

Chitinase — chitin degradation & plant immune priming

Breaks down chitin — the structural polymer found in insect exoskeletons, crustacean shells, and fungal cell walls. This serves two functions simultaneously. First, it releases nutrients locked in chitinous organic matter (insect frass, crustacean meal, fungal residues). Second, the chitin breakdown products trigger the salicylic acid defence pathway in plants — systemic acquired resistance (SAR) — priming the plant's immune system against fungal and insect attack. This is the same defence mechanism activated by neem meal and insect frass, but delivered through an enzymatic rather than a microbial route.

05

Urease — urea conversion

Hydrolyses urea into ammonium carbonate — converting this common organic nitrogen compound into plant-available ammonium. Urea is present in many organic fertilisers, animal manures, and is produced naturally by soil micro-organisms during protein metabolism. Urease from malted barley accelerates the conversion of urea to ammonium, making the nitrogen available to plants faster.

06

Cellulase — cellulose decomposition

Breaks down cellulose — the most abundant organic compound on Earth and the primary structural component of plant cell walls. Cellulose in dead plant material, mulch, straw, and woody compost must be enzymatically digested before its carbon and nutrients become available. Cellulase from malted barley accelerates this decomposition, working alongside the cellulase-producing fungi and bacteria already present in the soil.

07

β-Glucosidase — glucose release

Catalyses the final step of cellulose hydrolysis: the cleavage of cellobiose (a disaccharide intermediate) into glucose. Glucose is the universal energy currency for soil micro-organisms — its release from cellulose decomposition fuels the microbial activity that drives all nutrient cycling. β-glucosidase is often the rate-limiting enzyme in cellulose decomposition; supplementing it from malted barley removes this bottleneck.

08

Arylsulfatase — sulphur release

Breaks down organic sulphate esters, releasing plant-available sulphate (SO₄²⁻). Sulphur is the fourth major plant nutrient after nitrogen, phosphorus, and potassium — critical for protein synthesis, flavour development in brassicas and alliums, and amino acid production. Most soil sulphur is bound in organic forms that require enzymatic release. Arylsulfatase accelerates this, making organically bound sulphur available faster.

The catalyst effect — what diastatic power 250 means in practice

Diastatic power (DP) measures the total enzyme activity in malted grain, expressed in Windisch-Kolbach units. Standard malted barley used in brewing typically has a DP of 100–140. This product has a minimum DP of 250 — over 75% more enzyme activity per gram. In the soil, this means faster starch hydrolysis, faster protein breakdown, faster phosphorus liberation, and faster cellulose decomposition than standard malt. Every enzymatic reaction described above runs proportionally faster with higher DP malt. More enzyme activity per gram means more nutrient cycling per application.

Scientific References

  1. Dick, R.P. (1997). Soil enzyme activities as integrative indicators of soil health. In: Biological Indicators of Soil Health, CAB International, 121–156.
  2. Tabatabai, M.A. (1994). Soil enzymes. In: Methods of Soil Analysis, Part 2 — Microbiological and Biochemical Properties. SSSA Book Series 5, 775–833.
  3. Burns, R.G. et al. (2013). Soil enzymes in a changing environment. Soil Biology and Biochemistry, 58, 216–234.
  4. Briggs, D.E. (1998). Malts and Malting. Blackie Academic & Professional. [Enzyme production during germination and kilning]
  5. Bennett, J. (Clackamas Coot). (2020). Enzymes and Functions — malted barley in living soil. [Community research notes]

How to use malted barley: top dressing, soil mixing, worm bins & compost

Coarsely crushed — ready to apply

This product is pre-crushed to expose the enzyme-rich interior of the grain. Apply directly as a top dressing or mix into soil — no grinding required. For an even finer application, you can process further in a coffee grinder or food processor, but this is not necessary for most uses. Once crushed or ground, the enzymes are exposed to moisture and begin activating — for maximum freshness, use within a few weeks of opening.

Application rates

Soil mix — potting and container media

Rate: 10–20 ml per litre of soil  |  Frequency: Once when building the soil mix

Mix thoroughly into potting compost, living soil blends, or growing media before planting. The enzymes begin working as soon as the soil is watered, catalysing the breakdown of every organic ingredient in the mix — compost, worm castings, neem, seaweed, bone meal — into plant-available nutrients. This is particularly effective in living soil systems where the goal is to have nutrients cycling from the moment the plant goes in.

Top dressing — containers, pots and raised beds

Rate: 2–5 ml per litre of soil  |  Frequency: Weekly or as crop needs

Sprinkle evenly over the soil surface and water in well. Important: lightly mix the barley into the top centimetre of soil after application — if left sitting on the surface, it can form a hard crust as it absorbs moisture and dries. You may notice white mycelium (fungal threads) appearing on the soil surface after application — this is a positive sign indicating that the soil biology is actively colonising and digesting the barley. Regular weekly top dressing maintains a constant enzyme supply throughout the growing cycle.

Outdoor beds, borders and vegetable plots

Rate: 50–100g per m²  |  Frequency: Every 6 weeks during the growing season

Scatter over the soil surface and lightly rake or fork into the top 2–3 cm. Water in well. Apply alongside your regular organic fertiliser programme — the enzymes from the barley catalyse the breakdown of the fertiliser's organic nitrogen, phosphorus, and sulphur into plant-available forms, amplifying the speed and effectiveness of every fertiliser application.

At transplanting — root establishment boost

Rate: ½–1 teaspoon per plant  |  Frequency: Once at transplant

Sprinkle a small amount around the base of each transplant and water in. The enzyme-driven nutrient release and microbial stimulation creates ideal conditions for rapid root colonisation of new soil. Particularly effective for seedlings, rooted cuttings, and plants moved from small pots to their final positions.

Worm bin / vermicomposting

Rate: A generous sprinkling over the surface  |  Frequency: Weekly

Add malted barley to the top of your worm bin as a regular feed. The enzymes accelerate the breakdown of food waste and bedding material, while the sugars and proteins in the grain provide a concentrated food source for worms and the associated micro-organisms. Growers consistently report increased worm reproduction, faster castings production, and more biologically active finished vermicompost when barley is added regularly.

Compost heap accelerator

Rate: A few handfuls per barrowload of material  |  Frequency: Each time you add material

Sprinkle between layers of compost material. The enzyme suite accelerates the decomposition of every organic fraction in the heap simultaneously — cellulose, proteins, starches, chitin. The result is faster composting, higher biological activity, and a more nutrient-rich finished product.

Step-by-step application

  1. Measure the correct amount. For soil mixes: 10–20 ml per litre. For top dressing: 2–5 ml per litre. For beds: 50–100g per m². A tablespoon is approximately 8–10g of crushed barley.
  2. Scatter or mix evenly. For soil building, mix into the growing medium thoroughly. For top dressing, scatter over the surface and lightly work into the top centimetre of soil to prevent crusting.
  3. Water in well. The enzymes activate on contact with moisture. Watering also drives the released nutrients into the root zone.
  4. Repeat regularly for continuous enzyme supply. Enzymes are consumed in the reactions they catalyse and by microbial metabolism — they need regular replenishment. Weekly top dressing for containers; every 6 weeks for outdoor beds.
  5. Store sealed and dry. Keep in a sealed bag or airtight container in a cool, dry place. Once the grain is crushed, the exposed enzymes are vulnerable to moisture absorption — reseal immediately after each use. Store out of reach of birds and rodents, which are attracted to grain.
The white mycelium is a good sign

After applying malted barley as a top dressing, you may notice white fungal threads (mycelium) growing on the soil surface. This is beneficial fungi colonising and digesting the barley — exactly what you want. It means the soil biology is active and the enzyme-driven nutrient cycling process is working. Do not scrape it off or worry about it. If the mycelium becomes dense enough to form a crust, simply break it up with a light scratch and water in.

Works well combined with…

Malted barley is the catalyst that makes every other organic amendment work faster. Apply alongside Dr Forest granular fertilisers — Veg 4-4-4, Bloom 2-8-4, or All-Purpose 6-6-6 — and the enzymes will accelerate the release of nitrogen, phosphorus, and sulphur from the fertiliser. Combine with Grow-Kashi for the ultimate biological soil system: Grow-Kashi inoculates the living organisms, malted barley supplies the enzymes that feed them. Add to worm bins alongside Bokashi Bran scraps. Mix into living soil builds with Mineral Mix, Seaweed Meal, and Neem Meal — the barley enzymes will catalyse the breakdown of all of them simultaneously.

Frequently asked questions about malted barley

Diastatic power (DP) is a measure of the total enzyme activity in malted grain, expressed in Windisch-Kolbach (WK) units. "Diastatic" means the enzymes are alive and active — they were not destroyed during the malting and kilning process. Some malted barley is toasted, roasted, or heavily kilned for flavour (as used in dark beers) — this kills the enzymes and makes it non-diastatic and useless as a soil amendment. This product has a minimum DP of 250 WK — over 75% higher than standard diastatic malt (typically 100–140 WK). Higher DP means more enzyme activity per gram and faster nutrient cycling in the soil.
No — it is an enzyme catalyst and microbial food source. It contains some nitrogen, phosphorus, potassium, and trace minerals, but its primary value is the enzyme suite that accelerates the breakdown of organic matter into plant-available nutrients. Think of it as a speed multiplier for your existing fertiliser programme rather than a replacement for it. Use it alongside a balanced organic fertiliser for best results.
Sprouted seed tea is made by germinating fresh seeds in water — the sprouting process produces plant growth hormones (auxins, cytokinins, gibberellins) and some enzymes. Malted barley has been professionally germinated to the exact point of maximum enzyme production and then carefully dried to lock in those enzymes. The key difference: SST provides mainly hormones from the sprouting process; malted barley provides mainly enzymes from the malting process. They complement each other — hormones for growth stimulation, enzymes for nutrient cycling.
Yes — and it is one of the most effective additions you can make to a worm bin. The enzymes accelerate the breakdown of food waste and bedding material, while the sugars and proteins in the grain provide a rich food source for worms and their associated micro-organisms. Growers report increased worm reproduction, faster castings production, and more biologically active finished vermicompost. Add a generous sprinkling to the surface weekly.
Crushed barley grain absorbs moisture, swells slightly, and is then colonised by soil fungi (visible as white mycelium). If a dense layer is left on the surface without being worked in, this can dry into a crust. The solution is simple: lightly scratch the barley into the top centimetre of soil after applying and before watering in. This prevents crusting while keeping the grain in the biologically active surface layer of the soil. The white mycelium is beneficial — do not be concerned by it.
Yes — birds are attracted to grain. If growing outdoors, cover the soil surface with a light mulch layer after applying barley, or cover pots with a piece of hardware cloth or netting until the barley has been watered in and absorbed. Once the grain is moist and has begun to decompose, it is less attractive to birds. Indoor growers will not have this issue.
Excessive application can cause overly rapid microbial blooms — resulting in sour smells, surface slime, or a hydrophobic mulch layer. Stick to the recommended rates. If you notice any of these signs, pause applications for a week or two, scratch the surface, top with a thin layer of fresh compost, and resume at a lighter rate. At the recommended rates, over-application is very unlikely for most growers.
Store in a sealed bag or airtight container in a cool, dry place. Once crushed, the exposed enzymes are more vulnerable to moisture — reseal immediately after each use. Properly stored, the enzymes remain active for months. Keep out of reach of birds, rodents, and pantry moths, which are attracted to grain. If the grain absorbs moisture and begins to sprout or develop mould in storage, it is no longer suitable for use — discard onto the compost heap.
View full details
From 4,172 real Dr Forest orders

Often bought with this