Aluminium Sulphate | Soil Acidifier for Acid-Loving Plants | 500g
$ 19.99 – $ 129.90Price range: $ 19.99 through $ 129.90
- Turns Hydrangeas Blue: Supplies the aluminium pink and mauve hydrangeas need for vivid blue flowers
- Fast-Acting Soil Acidifier: Lowers soil pH far quicker than sulphur, ideal for acid-loving plants
- Fully Water Soluble: Dissolves quickly for easy soil drench application
- Phosphorus Free, No Fillers: Nothing to lock up aluminium, just high purity aluminium sulphate
Premium Aluminium Sulphate (Al₂(SO₄)₃) – Horticultural Grade Soil Acidifier
Our Premium Aluminium Sulphate (Al₂(SO₄)₃), also known as aluminium sulfate, is a white, fine crystalline powder designed for horticultural and gardening applications. It is water-soluble and provides a convenient way to acidify soil where a lower soil pH is required.
Aluminium sulphate is particularly popular with gardeners growing acid-loving plants such as hydrangeas, azaleas, camellias, rhododendrons and gardenias. It is also widely recognised for its role in encouraging blue or blue-purple colouring in suitable pink and mauve hydrangea varieties when soil conditions are appropriate.
Unlike elemental sulphur, which must be converted by soil microorganisms before its acidifying effect develops, aluminium sulphate can begin lowering soil pH once dissolved and incorporated into the soil. The actual response depends on the existing soil pH, soil type, application rate and plant requirements.
Instructions for Use
Dissolve the required amount in water and apply evenly to the soil around the established plant’s root zone. Water the soil before and after application where appropriate. Always test soil pH and follow recommended application rates for your plants and soil type.
For hydrangeas, aluminium sulphate is commonly used to help create the acidic soil conditions associated with blue flowers. Pink and mauve mophead and lacecap hydrangeas are the varieties most commonly capable of changing colour. White hydrangeas generally remain white, and flower colour is also influenced by variety, soil chemistry and other growing conditions. Changes may take time and are not guaranteed.
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Key Features & Benefits
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- Horticultural Grade: Suitable for gardening and horticultural soil-acidification applications
- Soil Acidifier: Helps lower soil pH where more acidic growing conditions are required
- Hydrangeas: Commonly used by gardeners seeking blue or blue-purple flowers on suitable hydrangea varieties
- Acid-Loving Plants: Suitable for plants such as azaleas, camellias, rhododendrons and gardenias when soil pH adjustment is required
- Water Soluble: Dissolves in water for convenient application as a soil treatment
- Phosphorus Free: Provides an option for gardeners who want to acidify soil without adding phosphorus
- Fast-Acting: Does not require the same microbial conversion process as elemental sulphur
- Fine Crystalline Powder: Easy to measure, dissolve and distribute when used according to recommended rates
- Convenient 500g Pack: A practical size for home gardens, potted plants and multiple applications
Common Gardening Applications
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- Lowering pH in alkaline or high-pH garden soils
- Preparing soil for acid-loving plants
- Hydrangea colour management
- Azaleas and rhododendrons
- Camellias and gardenias
- Other acid-loving ornamental plants
- Garden beds and established plants
- Potted plants where soil pH adjustment is required
Other Common Uses of Aluminium Sulphate
Aluminium sulphate is a versatile chemical compound with applications beyond gardening. Depending on the required grade, specification and applicable regulations, aluminium sulphate is commonly used in a range of industries and processes.
- Water Treatment: Used as a coagulant to help suspended particles and impurities aggregate and settle during water-treatment processes
- Paper Manufacturing: Used in certain papermaking processes and formulations
- Textile & Dyeing: Used in some textile processing and dyeing applications
- Industrial Processing: Used in various chemical, manufacturing and processing applications where its properties are required
- Gardening & Horticulture: Used as a soil acidifier and for hydrangea colour management
Important: This Green Pick product is supplied as a horticultural-grade product for gardening and horticultural applications. Although aluminium sulphate is used in other industries, suitability for drinking-water treatment, aquariums, swimming pools, food-related applications or other specialised uses depends on the required product grade, purity, certification and local regulations. Do not use this product for those applications unless its specification specifically confirms suitability.
Suitable For
- Home gardeners
- Garden enthusiasts and keen growers
- Horticultural applications
- Growing acid-loving plants
- Hydrangea growers
- Garden beds and ornamental gardens
- Potted plants requiring soil pH adjustment
Important Application Notes
Aluminium sulphate should be applied carefully because excessive soil acidity or excessive aluminium availability can harm plants. Soil type, existing pH, plant species and application rate all affect the result. Test your soil before application and avoid repeated heavy applications without monitoring pH.
For hydrangeas, aluminium sulphate alone does not guarantee blue flowers. Flower colour is affected by the hydrangea variety, soil pH, aluminium availability and other soil conditions. Always follow recommended application rates and avoid over-application.
Hazard Awareness
⚠️ Handle with care. Keep out of reach of children and pets. Avoid inhaling dust and avoid contact with eyes and skin. Wear appropriate gloves and eye protection when handling the powder. If dust or product enters the eyes, rinse thoroughly with clean water. Do not ingest. Not for human consumption.
When preparing a solution, use a suitable non-reactive container and avoid contact with sensitive surfaces or metals where corrosion may occur. Avoid unnecessary contact with plant foliage and rinse foliage promptly if significant splashing occurs. Store tightly sealed in a cool, dry place away from incompatible materials.
Why Choose Green Pick Aluminium Sulphate?
- ✅ Premium horticultural-grade aluminium sulphate
- ✅ Suitable for soil acidification and gardening applications
- ✅ Helps create acidic growing conditions for acid-loving plants
- ✅ Popular for hydrangea colour management
- ✅ Suitable for azaleas, camellias, rhododendrons, gardenias and other acid-loving plants
- ✅ Water-soluble crystalline powder
- ✅ Phosphorus free
- ✅ Convenient 500g resealable pack
- ✅ Suitable for home gardeners and horticultural use
- ✅ FREE Australia-wide shipping
| Weight | 500g, 5kg |
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