Zeolite is offered in four granulometries: extra-fine (0.5–1 mm), fine (1–3 mm), medium (3–6 mm), and coarse (6–9 mm), all in 25 kg bags with identical chemical composition (SiO₂ 68.6%, Al₂O₃ 12.4%, K₂O 2.8%, CaO 2.6%, among others). It is a natural mineral with microscopic alveolar porosity that provides very high cation exchange capacity (CEC), water and nutrient retention, and structural stability. Granulometry does not change the chemical properties, but it does define the application: from slow-release fertilizer to water drainage and filtration.
🎯 Choose your variant in 10 seconds
- If your case is field crop amendment, fertigation, or lawn: go to extra-fine (0.5–1 mm)
- If your case is seedbeds, horticultural substrates, or small pots: go to fine (1–3 mm)
- If your case is large pots, gardening, or cocopeat mixes: go to medium (3–6 mm)
- If your case is drainage, water filtration, or odor control: go to coarse (6–9 mm)
What to consider before choosing a variant
All four granulometries are chemically identical and provide the same functional properties: high CEC, water and nutrient retention, structural stability, and alveolar porosity. The choice is based only on how the particle interacts with the crop, soil, or system:
- Agronomic application: In field crops and lawns, extra-fine or fine is incorporated into the soil or fertigation because it mixes well with soil and acts as a nutrient reservoir. In pots and formulated substrates, medium and coarse maintain structure and provide drainage without compacting.
- Non-agronomic application: Coarse zeolite is used in water filtration (aquariums, small treatment plants, ponds), in odor absorption in stables or chicken coops, and as a medium for decontaminating soils with heavy metals or ammonia. For these uses, a large particle is always preferable.
- Cation exchange capacity (CEC): Zeolite has high CEC in all its granulometries (the more exposed surface, the faster the exchange rate, but the total amount of exchangeable cations per gram is similar). Extra-fine releases nutrients faster; coarse releases them more slowly.
- Ammonium retention (NH₄⁺): Zeolite has a specific affinity for ammonium, which makes it very effective in reducing nitrogen leaching when applied with fertilizers. This property works across all granulometries.
- Mixing with other substrates: Fine and medium are combined with peat, cocopeat, or vermicompost in proportions of 5–20% to improve nutrient retention in nursery or vegetable substrates. Coarse is rarely used in mixes; it is more for filtration and drainage.
Extra-fine granulometry (0.5–1 mm): for field amendment and fertigation
- Homogeneous mixing with soil and compost
- Rapid ion exchange rate
- Ideal for top dressing on lawns
- Applicable for base and top dressing fertilization
- Generates more dust when handled dry
- Not suitable for drainage or water filtration
Extra-fine zeolite is the standard option for extensive agricultural use. It is incorporated into the soil during seedbed preparation (0.5–2 t/ha contribution), added to compost to reduce nitrogen losses due to ammonia, or applied as top dressing on lawns (50–100 g/m²) after scarification to improve nutrient and water retention. In fertigation with nitrogen fertilizers, extra-fine zeolite mixed with the base substrate significantly reduces leaching losses.
Fine granulometry (1–3 mm): for seedbeds and horticultural substrates
- Compatible with trays and planters
- Provides CEC without compacting the substrate
- Works well at 5–10% in mix
- Reduces irrigation frequency in seedlings
- Generates some dust when handled dry
- Oversized for field amendment
Fine zeolite is the commercial nursery's choice for formulated substrates. Mixed at 5–10% with peat or cocopeat, it provides cation exchange capacity to the base substrate without altering its physical structure. This reduces the frequency of fertigation and minimizes leaching losses, especially in seedling trays where irrigation is very frequent. It is also used in hydroponics as a buffer medium to stabilize the pH of the nutrient solution.
Medium granulometry (3–6 mm): the standard for pots and cocopeat mixes
- Long-term structural stability
- Provides drainage + nutrient retention
- Works well at 10–20% in cocopeat
- Suitable as a middle layer in large pots
- Leaves empty spaces in small trays
- Not optimal for extensive amendment
Medium zeolite is the versatile option for medium and large pots, deep planters, and mixes with cocopeat or peat. It combines the advantages of fine (high CEC, nutrient retention) with those of coarse (drainage, structural stability). Mixed at 10–20% with cocopeat, it is excellent for bagged vegetables, greenhouse tomatoes, and plants that receive frequent fertigation. It is also used as an intermediate drainage layer in pots larger than 20 L.
Coarse granulometry (6–9 mm): for drainage, filtration, and odors
- Suitable as a filter medium in ponds
- Absorbs ammonia and reduces odors in corrals
- Fast drainage in large pots
- Generates very little dust when handled
- Not ideal for seedbeds or seedlings
- Oversized for agricultural amendment
Coarse zeolite is the option for non-agricultural uses where drainage, filtration, and gas absorption are important. As a filter medium in aquariums and ponds, it retains ammonia and improves water quality. Spread on the ground of chicken coops, stables, or pigsties, it absorbs ammonia produced by fresh manure and reduces odors. In gardening, it functions as a drainage layer at the bottom of large pots (3–5 cm) and, mixed with gravel, in garden drainage systems for construction.
Comparative table of variants
All four granulometries are chemically identical (same composition of SiO₂, Al₂O₃, K₂O, CaO, etc.) and come in 25 kg bags. The difference lies only in the grain size and, therefore, in the application where it is most effective.
| Feature | Extra-fine | Fine | Medium | Coarse |
|---|---|---|---|---|
| Ideal use | Field crop | Seedbeds | Large pots | Drainage and filtration |
| SKU | 858964 | 384712 | 875269 | 886800 |
| Grain size | 0.5–1 mm | 1–3 mm | 3–6 mm | 6–9 mm |
| Exchange rate | Fast | Medium-high | Medium | Slow |
| Drainage | Slow | Medium | Fast | Very fast |
| Suitable for filtration | — | — | Limited | Yes |
| SiO₂ composition | 68.6 % | 68.6 % | 68.6 % | 68.6 % |
| Al₂O₃ composition | 12.4 % | 12.4 % | 12.4 % | 12.4 % |
| Weight per bag | 25 kg (55.1 lb) | 25 kg (55.1 lb) | 25 kg (55.1 lb) | 25 kg (55.1 lb) |
Use case matrix → recommended variant
| If your case is… | Recommended variant |
|---|---|
| Top dressing for extensive lawns or gardens | → Extra-fine |
| Improving compost or reducing N losses in fertilization | → Extra-fine |
| Improving seedling substrate in trays | → Fine |
| Substrate for bag-grown vegetables or greenhouse tomatoes | → Medium |
| Large pots with coco peat or peat | → Medium |
| Filtration in ponds, aquariums, or aquatic systems | → Coarse |
| Reducing ammonia odor in chicken coops or stables | → Coarse |
| Drainage layer in very large pots | → Coarse |
Take advantage of zeolite's affinity for ammonium to optimize your nitrogen fertilization. Apply extra-fine zeolite along with urea or ammonium sulfate to the soil: the zeolite will capture the ammonium released during hydrolysis and retain it in its cation exchange sites, where the plant will gradually absorb it. This reduces volatilization to the atmosphere (especially important in hot climates) and leaching by irrigation, resulting in significantly higher N efficiency and lower fertilizer use per season.
Do not use extra-fine zeolite in potting substrates for container plants. The 0.5–1 mm particle tends to settle to the bottom of the pot with each watering, where it compacts and blocks drainage. For pots, always use granular sizes of 1–3 mm or larger, which maintain their position and provide structure without clogging the substrate.
What zeolite particle size do you need?
Tell us what you want to use it for (extensive cultivation, nursery substrate, gardening, filtration, odor control) and the approximate amount you need. You will receive the exact particle size and recommended dosage for your case.
Frequently asked questions
Does zeolite provide nutrients to plants?
Zeolite itself is not a fertilizer: it provides very small amounts of potassium, calcium, and other cations from its composition over time. Its real value lies in its cation exchange capacity (CEC): it retains nutrients provided by the fertilizer and releases them gradually, preventing losses due to leaching. It is a supplement to fertilizer, not a substitute.
Can zeolite be regenerated after use?
Yes, especially in filtration applications. When it has been saturated with ammonium (in aquarium filters or chicken coops), zeolite can be regenerated by washing it with a 5–10% saline solution (sodium chloride or potassium chloride): the sodium or potassium displaces the retained ammonium, and the zeolite is ready to be used again. Rinse thoroughly before reusing. In agricultural applications, regeneration is not necessary; the exchanged nutrients pass to the plants.
Zeolite or vermiculite for nutrient retention?
Both retain nutrients and water, but zeolite offers greater CEC and specificity for ammonium (a key affinity in nitrogen fertilization). Vermiculite is lighter, retains more water per unit volume, and is preferred in substrates where weight matters. Zeolite is heavier and structurally stable, ideal in horticultural mixes to reduce fertilizer leaching.