Copper Sulphate Blue Stone 1kg to 25kg – Fungicide, Algaecide & Root Killer

Copper Sulphate Blue Stone 25kg: Multi-Purpose Fungicide, Algaecide & Root Treatment

Copper Sulphate, also known as bluestone or blue vitriol, is a bright blue crystalline compound (copper sulphate pentahydrate) with a wide range of uses across agriculture, horticulture, water treatment and industry. It dissolves readily in water and is valued as an economical fungicide, algaecide and copper source, which is why it's been a staple product for growers, landholders and tradespeople for generations.

Main Uses

Fungicide: Copper sulphate controls a range of fungal and bacterial plant diseases such as downy mildew, leaf spot and blight. It's most commonly used to make Bordeaux Mixture, a traditional copper-and-lime spray for vines, fruit trees and berries. A standard Bordeaux mix is around 100 g copper sulphate plus 100 g hydrated lime per 10 L of water.

Algaecide: It controls algae in dams, ponds, reservoirs and irrigation channels. Only very small amounts are needed, and copper levels must be kept low to protect fish (see the caution below).

Copper deficiency: It's used to correct copper deficiency in soils and plants, and copper sulphate solutions are also used in livestock footbaths for footrot and hoof issues, best done under veterinary guidance.

Root and drain treatment: Copper sulphate crystals are sometimes used to control invasive tree roots in drains and sewer lines. Important: this use is restricted or banned in some areas, and copper sulphate can corrode metal pipes, so check your local regulations and plumbing before using it this way.

Industrial: It's also used in electroplating, wood preservation and in manufacturing other copper-based chemicals.

How to Use

Copper sulphate is highly soluble, so dissolve the crystals fully in water before applying. Dilution depends entirely on the job:

• Plant fungicide (Bordeaux mix): around 100 g copper sulphate + 100 g lime per 10 L water

• Pond algae: very dilute only, keeping dissolved copper well under about 0.2 ppm to avoid harming fish

• Footbath (livestock): typically a 2 to 5% solution, under veterinary advice

• Root treatment: follow local regulations and product directions

Always follow the recommended rate for your specific use, and don't over-apply, as more is not better with copper.

Key Features & Benefits

• Copper sulphate pentahydrate (bluestone) in soluble blue crystal form

• Multi-purpose fungicide, algaecide, copper source and root treatment

• Makes traditional Bordeaux Mixture for fruit trees, vines and berries

• Controls algae in dams, ponds and irrigation channels

• Corrects copper deficiency in soils and plants

• Used across agriculture, horticulture, water treatment and industry

• Available in 1kg, 2kg, 4kg and 25kg

Frequently Asked Questions

What is copper sulphate bluestone?
It's copper sulphate pentahydrate (CuSO₄·5H₂O), a bright blue, water-soluble crystalline compound also called bluestone or blue vitriol. It's used as a fungicide, algaecide, copper source and root treatment.

Why is copper sulphate blue?
The bright blue colour comes from the hydrated (pentahydrate) form, where water molecules are bound into the crystal structure. The anhydrous form, without that water, is a pale green-white powder instead.

How do I use copper sulphate as a fungicide?
The most common method is Bordeaux Mixture: dissolve around 100 g copper sulphate and 100 g hydrated lime per 10 L of water and spray onto plants. Use it preventively, and always follow label rates to avoid leaf and fruit damage.

How do I use copper sulphate for pond algae?
Use only very small amounts dissolved in water, keeping dissolved copper well below about 0.2 ppm. Copper is toxic to fish, so overdosing can cause fish kills. For stocked ponds, get advice from a pond specialist first.

Can I use copper sulphate to kill tree roots in drains?
It's sometimes used for this, but the use is restricted or banned in some areas and it can corrode metal pipes. Check your local regulations and your plumbing type before considering it.

Is copper sulphate safe to handle?
It's a poison that can be absorbed through the skin and is corrosive to metals. Wear gloves, eye protection and a mask, wash your hands after use, keep it away from children, pets and waterways, and store it sealed and dry.

What sizes does it come in?
It's available in 1kg, 2kg, 4kg and 25kg, with the 25kg pack suited to farms, larger properties and commercial use.