Agril Volcanic Substrate — Semi-Hydroponic Propagation Medium for Tissue Culture, Alocasia Corms and Stem Cuttings
Original price was: රු1,799.00.රු1,499.00Current price is: රු1,499.00.
Agril Volcanic Substrate is a porous, low-dust volcanic granule medium purpose-built for three high-precision growing situations: acclimating tissue culture plantlets from agar to soil conditions, rooting small stem cuttings in a semi-hydroponic environment, and germinating Alocasia corms where consistent moisture at the base and open aeration above it are both critical. Each granule holds moisture within its porous structure while maintaining stable air gaps between particles — giving roots the wet-dry cycling they need without the compaction risk of fine media.
pH approximately 6.5–7.0 (slightly acidic to neutral). Dark volcanic granule, 2–3mm particle size. Low dust — sieved before packing. Net weight 1 kg. Sterile. Suitable for semi-hydroponic passive reservoir setups, propagation trays, and transition containers.
Three high-failure situations that most substrates handle badly
Tissue culture plantlets, Alocasia corms, and small stem cuttings each fail for the same underlying reason in standard growing media: the substrate either holds too much moisture (causing rot at the root or corm base) or dries out unevenly (causing die-back during establishment). Fine media like coco peat or potting soil retain water in a dense matrix that offers little aeration — the exact opposite of what fragile new roots need. Volcanic Substrate solves this with a porous granule structure that holds moisture inside each particle while maintaining permanent air gaps between them. Roots and corms sit in a stable, evenly humid environment without ever being waterlogged.
The near-neutral pH (6.5–7.0) also matters here. Tissue culture plants are removed from a sterile, chemically buffered agar environment — transferring them directly into acidic or alkaline substrate stresses them further. Volcanic Substrate’s stable, near-neutral chemistry keeps that transition as smooth as possible.
What’s in the pack
- Agril Volcanic Substrate — dark volcanic granule, 2–3mm particle size, low dust (sieved before packing). Net weight: 1 kg.
- Condition — dry packed, sterile. Rinse before first use to remove any remaining fine particles.
- pH — 6.5–7.0, slightly acidic to neutral. Stable and consistent across the granule.
What you can use it for
- Tissue culture acclimation — transfer TC plantlets from agar directly into damp Volcanic Substrate in small propagation cups. The porous granules maintain high humidity at root level while allowing gas exchange — critical during the first 2–4 weeks out of sterile agar conditions.
- Alocasia corm germination — press corms just below the surface in damp Volcanic Substrate with a passive reservoir below. The granules wick moisture upward to the corm base while the surface layer stays open and aerated, preventing the fungal rot that kills corms in dense media.
- Small stem cutting propagation — insert cuttings into damp Volcanic Substrate in clear propagation cups or small pots with drainage. Roots develop along the granule surface and through pore spaces with excellent gas exchange at every stage.
- Semi-hydroponic transition substrate — use as an intermediate medium when transitioning established plants from soil to LECA. The slightly finer granule size than LECA provides more surface contact for transitioning roots.
Preparing the substrate before use
- Rinse in a fine-mesh colander under running water for 30–60 seconds. Even after sieving, some fine particles are released during shipping. Rinsing until water runs clear gives you a clean, consistent granule bed with no dust that would clog pore spaces.
- Pre-moisten before filling containers. Add a small amount of clean water to the rinsed substrate and mix — granules should feel evenly damp throughout but not dripping. Pre-moistening ensures consistent humidity across the entire medium from day one, rather than relying on capillary action to distribute moisture after potting.
- Fill your propagation cup or tray loosely to within 1–2cm of the rim. Do not compress — the air gaps between granules are the medium's primary advantage; compacting removes them.
Tissue culture plantlet acclimation
- Remove the plantlet from its agar container and rinse roots very gently under room-temperature water to remove all traces of agar gel. Agar left on roots supports fungal and bacterial growth in the substrate.
- Create a small cavity in the centre of the pre-moistened substrate with a pencil or thin tool — just wide enough for the root mass without forcing it.
- Place the plantlet with roots sitting naturally in the cavity. Gently press substrate around the base to ensure root contact. Do not bury the crown — keep it at or just above the substrate surface.
- Enclose in high humidity immediately — a clear plastic bag, propagation dome, or humidity chamber at 80–90% RH. TC plants have no cuticle development and lose water through leaves rapidly; humidity control is more critical than the substrate choice in the first two weeks.
- Reduce humidity gradually from week 3 onwards — open the dome for 1–2 hours per day, increasing by 1–2 hours each week. Full ambient humidity acclimation typically takes 4–6 weeks depending on species.
- Begin diluted liquid fertiliser at week 3–4 once new leaf growth is visible — start at 25% of the recommended dose and increase weekly. The substrate provides no nutrition; plants need nutrient input once agar reserves are depleted.
Alocasia corm germination
- Fill a small clear pot (8–10cm diameter with drainage holes) to within 3cm of the rim with pre-moistened Volcanic Substrate.
- Place the corm with the flat/root end down and the pointed tip just at or 3–5mm below the substrate surface. Do not bury deeply — corms need warmth and light to trigger sprouting and rot quickly when buried in dense, wet media.
- Set up a passive reservoir — sit the pot in a saucer with 1–2cm of clean water. The Volcanic Substrate wicks moisture upward to the corm base by capillary action. Refill the reservoir when empty rather than top-watering — top-watering disturbs the corm and creates uneven moisture.
- Maintain warmth — 26–30°C is ideal for Alocasia corm germination. A heat mat beneath the pot significantly improves germination speed and success rate. Avoid temperatures below 22°C during germination.
- Watch for the first sprout — typically 2–5 weeks depending on corm size, species, and temperature. Once a leaf has unfurled to 3–4cm, begin diluted liquid fertiliser at 25% strength.
Small stem cutting propagation
- Take your cutting with at least one node, trim any large leaves to reduce transpiration, and allow cut surfaces to air dry for 30–60 minutes before inserting.
- Insert the cutting 3–5cm deep into pre-moistened Volcanic Substrate. The granules provide enough stability to hold the cutting upright without staking for most species.
- Set up as semi-hydroponic — sit the propagation cup in a small reservoir of clean water (1–2cm depth). Roots will develop along the granule surfaces and downward toward the water source.
- Monitor for root development through clear cup walls — roots are typically visible within 2–4 weeks for fast-rooting species. Do not disturb the cutting to check roots; wait for visible growth through the cup wall.
- Transition to a full substrate once roots are 3–5cm long and well-branched. Tip the cup gently — the granules release cleanly from roots without tearing.
Tips for best results
- Use clear propagation cups for all three applications — the ability to monitor root development, corm sprouting progress, and moisture level at depth without disturbing the plant is the single biggest advantage in propagation work.
- Change reservoir water weekly to prevent algal and bacterial build-up in the standing water. A few drops of 3% hydrogen peroxide per litre of reservoir water helps keep it clean without harming roots.
- Keep temperatures above 24°C — Volcanic Substrate performs best as a propagation medium in warm conditions. Below 20°C, root initiation slows significantly regardless of substrate.
- Do not fertilise TC plants in their first 2–3 weeks — they are still drawing on agar nutrient reserves and root systems cannot yet process external nutrient inputs. Premature fertilising causes tip burn and set-back.
Volcanic Substrate vs LECA — same principle, different jobs
Both Volcanic Substrate and LECA (clay pellets) are inert, porous semi-hydroponic media that hold moisture internally and maintain air gaps between particles. They are not interchangeable — they are optimised for different growth stages and plant sizes. Understanding when each is the right choice will save you failed propagations and unnecessary repots.
| Feature | Volcanic Substrate | LECA Clay Pellets |
|---|---|---|
| Particle size | 2–4mm — fine granule | 8–16mm — coarse pellet |
| Root contact surface | Very high — fine particles create more surface for new root tips | Lower — larger gaps between pellets suit developed root systems |
| Best growth stage | Propagation & establishment — cuttings, corms, TC plants | Mature plants — established root systems in semi-hydro |
| pH | 6.5–7.0 (slightly acidic to neutral) | 6.5–7.0 (neutral) |
| Moisture retention | Higher — finer particles retain more moisture per volume | Lower — larger granules drain faster between waterings |
| Aeration | Good — smaller pore spaces | Very high — large inter-pellet gaps suit mature, thick roots |
| Visibility through clear pots | Excellent — fine granules let you see corm and root emergence clearly | Good — but large gaps can obscure early root tips |
| Reusability | Limited — sterilise and reuse 1–2 times | Indefinite — wash, sterilise, reuse permanently |
| Cost per use | Low upfront — higher per cycle if not reusing | Very low long-term — lasts indefinitely |
| Nutrient source | None — inert | None — inert |
Which should you choose?
- Germinating Alocasia or Caladium corms
- Acclimating tissue culture plantlets from agar
- Rooting small stem cuttings semi-hydroponically
- Working with very small or fragile root systems
- You need fine granule contact for early root establishment
- Running a long-term semi-hydroponic system for mature plants
- Growing established aroids, pothos, or Hoyas in passive hydro
- You want a reusable, indefinitely stable medium
- Working with plants that have thick, developed root systems
- Cost-per-use over multiple years is a priority
Is this the same as Fluval Stratum? What's the actual material?
Agril Volcanic Substrate uses the same volcanic granule material as Fluval Stratum — a fired, porous volcanic soil granule mined from the foothills of Mount Aso in Japan. We repackage it in 1 kg Agril-branded pouches, sieved to remove dust before packing. The material itself is identical. If you've used Fluval Stratum for aquatic plants or shrimp tanks, the substrate you're receiving is the same granule — the difference is that we're supplying it for terrestrial propagation use rather than aquarium applications.
My Alocasia corm has been in the substrate for 3 weeks with no sign of sprouting — is something wrong?
Not necessarily. Alocasia corm germination is temperature-dependent more than substrate-dependent. Below 24°C, germination can stall for weeks. The two most reliable fixes: add bottom heat (a heat mat set to 28–30°C) and check that the corm tip is at or just at the surface level — buried corms sprout significantly more slowly. Also check the corm itself: a healthy corm is firm with no soft spots and a slightly pointed tip. If it's soft, shrivelled, or smells off, it may have failed before planting.
Can I reuse Volcanic Substrate after a propagation cycle?
Yes, with sterilisation. After removing the plant, rinse the granules thoroughly and soak in a diluted hydrogen peroxide solution (3% H₂O₂, 1 part to 10 parts water) for 30–60 minutes, then rinse again with clean water and allow to air dry. This eliminates residual biological material and resets the substrate for the next use. We recommend a maximum of 2–3 reuse cycles before replacing — granule structure degrades over time and fine particles accumulate that reduce aeration between cycles.
What nutrient solution should I use in the reservoir for semi-hydroponic propagation?
For cuttings and corms in the early germination/rooting phase, use plain clean water in the reservoir for the first 2–4 weeks — roots and corms do not need or benefit from nutrients during initial establishment, and nutrient salts in early-stage reservoirs can cause tip burn and set-back. Once you see clear root development or the first new leaf, switch to a diluted balanced liquid fertiliser at 25% of the recommended dose. Increase to 50% at week 6–8 and to full strength only once the plant is actively growing with multiple established leaves.
I see green algae growing in my clear propagation cups — should I be concerned?
Algae growth in clear cups is cosmetic and generally harmless to roots and corms in the short term. It competes mildly for nutrients in the reservoir water but does not directly harm plant tissue. Prevent it by reducing light reaching the lower portion of the cup — wrap the lower half in opaque tape or foil, or use opaque outer pots. Adding 2–3 drops of 3% hydrogen peroxide per 100ml of reservoir water at each refill suppresses algae without affecting root development.
Can I use this for seeds as well as corms and cuttings?
For larger seeds (Monstera, Philodendron, Anthurium), yes — the 2–4mm granule size provides good surface contact for large seeds placed on top and pressed lightly into the surface. For small or fine seeds (Begonia, Gesneriad, fine orchid seeds), the granule size is too coarse — seed will fall between particles without consistent contact. Fine sphagnum moss or a dedicated seed-sowing medium is more appropriate for very small seeds.
How does the pH of 6.5–7.0 compare to what TC plants are used to in agar?
Standard plant tissue culture agar is typically formulated at pH 5.7–5.8 — slightly more acidic than Volcanic Substrate's 6.5–7.0. The difference is small enough that most TC plants tolerate the transition without visible stress. If you're working with particularly pH-sensitive species or noticing consistent yellowing at the new leaf stage after transfer, you can adjust the substrate pH downward by watering with slightly acidified water (a drop of citric acid solution per litre brings it toward 6.0). For the vast majority of tropical aroids and houseplants, the 6.5–7.0 range is well within the acceptable window.
The label says "low dust" — does this mean I don't need to rinse it?
Rinsing is still recommended even though the substrate has been sieved before packing. The sieving process removes the bulk of fine particles, but some dust is generated during bag filling, sealing, and shipping as granules shift and rub against each other. A 30–60 second rinse under running water in a fine-mesh colander removes these residual fines and gives you the cleanest possible granule bed. It also pre-moistens the substrate evenly, which is the correct starting condition for all three primary use cases.
Full product specifications
Physical Properties
| Material | Porous volcanic soil granule (fired volcanic mineral) |
| Particle size | 2–3mm |
| Colour | Dark brown to near-black |
| Structure | Porous internal matrix — high water absorption per granule |
| Dust content | Low — sieved before packing; rinse before use |
| Density (dry) | Approx. 0.55–0.75 g/cm³ |
Chemical Properties
| pH range | 6.5–7.0 (slightly acidic to neutral) |
| EC | Very low — essentially inert |
| Ammonia | Releases trace ammonia initially — rinse before first use |
| Nutrient content | Minimal — not a fertiliser or amendment |
| Chemical reactivity | Low — stable, does not alter fertiliser or reservoir chemistry significantly |
| Sterility | Sterile as packed — rinse maintains sterility before use |
Primary Applications
| Tissue culture acclimation | Yes — near-neutral pH eases transition from agar |
| Alocasia corm germination | Yes — passive semi-hydroponic reservoir method |
| Stem cutting propagation | Yes — semi-hydroponic or damp packed |
| Mature plant long-term use | Not recommended — no nutrition; transition to full substrate |
| Aquarium use | Compatible — same material as Fluval Stratum aquatic substrate |
| Suitable plant types | Aroids, Alocasia, TC plantlets, Hoyas, small tropical cuttings |
Semi-Hydroponic Setup
| Reservoir water depth | 1–2cm below pot base |
| Capillary wicking | Good — fine granule wicks moisture upward effectively |
| Recommended reservoir change | Weekly — prevent algal and bacterial build-up |
| Compatible pot types | Clear propagation cups, net pots, standard pots with drainage |
| Nutrient solution | Clean water for first 2–4 weeks; diluted liquid fertiliser thereafter |
Reusability
| Reusable | Yes — sterilise with diluted H₂O₂ between uses |
| Recommended reuse cycles | 2–3 cycles maximum before replacing |
| Degradation | Gradual — granule structure softens over multiple cycles |
Packaging
| Net weight | 1 kg |
| Pack type | Sealed kraft paper stand-up zip-lock pouch with clear window |
| Condition at dispatch | Dry — rinse and pre-moisten before use |
| Shelf life (sealed, dry) | Indefinite |
| Warranty | No warranty — consumable propagation medium |
Only logged in customers who have purchased this product may leave a review.
Frequently bought together
Agril Volcanic Substrate — Semi-Hydroponic Propagation Medium for Tissue Culture, Alocasia Corms and Stem Cuttings
Agril Volcanic Substrate is a porous, low-dust volcanic granule medium purpose-built for three high-precision growing situations: acclimating tissue culture plantlets from agar to soil conditions, rooting small stem cuttings in a semi-hydroponic environment, and germinating Alocasia corms where consistent moisture at the base and open aeration above it are both critical. Each granule holds moisture within its porous structure while maintaining stable air gaps between particles — giving roots the wet-dry cycling they need without the compaction risk of fine media.
pH approximately 6.5–7.0 (slightly acidic to neutral). Dark volcanic granule, 2–3mm particle size. Low dust — sieved before packing. Net weight 1 kg. Sterile. Suitable for semi-hydroponic passive reservoir setups, propagation trays, and transition containers.
Agril BioBoost Coco Chips — Trichoderma-Enriched 10–20mm Coconut Husk for Orchids and Aroids
BioBoost Coco Chips combine the macroporous drainage structure of 10–20mm coconut husk chunks with supplier-blended enrichments: a Trichoderma-based biological fungicide, plant-derived rooting hormone, and a balanced starter fertiliser — giving roots both the physical space to expand and the biological environment to establish faster.
Chip size 10–20mm. pH 5.5–6.8. Low EC. Sterile base. No additional fungicide treatment required for the first 6–8 weeks. Purpose-built for orchids, aroids, and epiphyte mixes where establishment speed and root health matter.
Agril BioBoost Coco Peat — Trichoderma-Enriched, Rooting Hormone & Starter Fertiliser Blended Growing Medium
BioBoost Coco Peat is premium pH-buffered coco peat pre-enriched with a Trichoderma-based biological fungicide, plant-derived rooting hormone, and a balanced starter fertiliser — delivering a substrate that actively supports root development, suppresses soil-borne pathogens, and provides early nutrition from day one. It is the ready-to-use choice for propagation, repotting aroids, and establishing newly potted tropicals.
pH buffered to 5.8–6.5. EC flushed to below 1.0 mS/cm prior to enrichment. Sterile base medium. No additional fungicide treatment required for the first 6–8 weeks of use.
Agril Horticultural Grade Perlite (3–6mm) — Zip-lock Pouch
Most plant roots drown long before they dry out. Perlite is the simplest way to add instant drainage and essential air pockets to heavy potting soils, keeping your tropicals and succulents breathing comfortably.
These lightweight volcanic glass pearls prevent soil compaction while holding onto nutrients for slow release. It sits at a neutral pH, making it completely safe for sensitive roots. Just remember to dampen it before mixing—dry perlite dust isn't something you want to breathe in.
Burned Rice Husk — Carbonised Rice Hull Biochar, Permanent Drainage Amendment, Sterile
Burned rice husk is fully carbonised rice hull — a black, lightweight biochar material produced by controlled high-temperature combustion of paddy husks. Its porous carbon matrix improves drainage, increases aeration, and provides long-lasting physical structure in any substrate blend. Unlike organic amendments, carbonised rice hull does not decompose and contributes stable, permanent porosity to the mix.
pH approximately 7.0–8.5 (slightly alkaline). Sterile. Weed-free. Long-lasting structural amendment. Use at 10–20% by volume in mixed substrates. Pair with worm castings or fertiliser for nutrition — carbonised husk is not a nutrient source.
Worm Castings — Pure Vermicompost, Slow-Release Organic Nutrition, Odour-Neutral
Worm castings are the finished vermicompost output of earthworms processing organic matter — a dense, nutrient-rich amendment that feeds soil biology, improves structure, and provides gentle slow-release nutrition without burn risk at recommended ratios. Unlike synthetic fertilisers, castings simultaneously improve microbial activity, water retention, and nutrient availability.
NPK approximately 1–0.7–1.1 with a rich micronutrient and humic acid profile. Odour-neutral. Safe for all plants including seedlings. Use at 10–20% by volume in any substrate blend or as a top-dress amendment.
Indoor Plant Repotting Mat | Waterproof & Foldable
Keep your floors and tables clean with this waterproof indoor plant repotting mat. Unfold it, snap the corners together, and create an instant, mess-free workspace for repotting, pruning, or mixing soil. Measuring 50cm × 50cm, it is perfectly sized for apartment dwellers and kitchen counters.
Made from flexible, water-resistant PE material, it reliably catches stray dirt and water spills. When you are done, simply unclip one corner to funnel excess soil back into your bag, wipe it down, and fold it away for easy storage.
Related products
Baked Rice Husk — Kiln-Dried Sterilised Rice Hull, Near-Neutral pH, Lightweight Drainage Amendment
Baked rice husk is kiln-dried and sterilised paddy hull — golden-tan in colour, not carbonised, retaining its natural silica-reinforced structure while being rendered sterile and weed-free. It provides lightweight bulk, modest drainage, and short-to-medium-term aeration in substrate blends. A practical, sustainable, and low-cost amendment derived from an agricultural by-product.
pH approximately 6.0–7.0 (near-neutral). Sterile. Lightweight. Gradually biodegradable over 12–18 months. Use at 15–25% by volume in tropical, seedling, and succulent substrate mixes. Refresh or repot substrate when breakdown is visible.
Horticultural Charcoal — Sustainably Sourced Selected Hardwood, Toxin Adsorption, Terrarium Grade
Agril Horticultural Charcoal is produced by slow-burning selected hardwoods chosen specifically for their low resin content and clean burn profile — resulting in a pure, mineral-rich carbon amendment free from resinous contaminants. The porous carbon structure adsorbs excess salts, organic waste compounds, and volatile impurities that accumulate in closed or low-drainage container environments, helping maintain substrate freshness over time.
pH approximately 7.0–8.5. Sustainably sourced hardwood. Use at 5–10% in terrariums, closed systems, and any substrate where long-term hygiene and toxin control are priorities. Not a substitute for activated carbon in aquatic systems.
Shop All HousePlants
Reviews
Clear filtersThere are no reviews yet.