Using Expanded Clay Balls….




Firstly, what are expanded clay balls and how are they made. They are made from top quality clay medium. The clay is made into clay pellets and are heated to 1200/2000 degrees Fahrenheit. The interior is expanded to a sponge-like form, which provides exceptional absorption of water and nutrients, while the Page underis more densified, providing strength, while limiting salt buildup. They are inorganic, sterile and will not compact, decompose or harbor mold or disease. Its regular shape promotes good air circulation in the root zone, which creates a stronger root system and a healthier plant. It allows humidity around the plant. cross section of clay balls

Cross Section of Clay Balls


Prior to first use, rinse the clay balls with clean water to remove any dust particles that has built up during shipment. I then soak the balls in a mixture of Algonox (5mls to a litre) and Calcium Nitrate (1 gram to a litre) for one hour, they are then ready to use. You can use a rooting solution at the rate of ½ teaspoons per 4 ltrs I do not fill the pot to the top; I leave about 10 mm free at the top, helps to keep the roots in the pot


There are a number of ways to use the balls and this is done by using different pots. three with wire

Use a pot with drain holes in the base, put a layer of balls in the bottom of the pot, add plant and balls and grow as with any other potting material. You will need to stabilize the plant, as the clay balls are too light to hold the plant, until the new roots secure it. I use a wire loop attached to the sides of the pot, as per photo. Secure the plant to the wire loop.     Using the same pot as above, pot the plant, always put a layer of balls in first, this stops the roots from going directly into the reservoir, when first repotted, again with the wire loop to secure the plant, place the pot in a plastic saucer, with a depth of 15/20 mm, to hold water/fertilizer etc., this will act as a reservoir and feed the plant continuously. It will also create humidity and help the plant from dehydrating and keep it cooler. As per photo.

    two pots two holes

  In this method, a pot with no drainage holes is used. I drill four drainage holes,(3/16) parallel to the base of the pot, in the side walls, each hole approximately a quarter of the way around the pot, about 15mm from the bottom of the pot. This leaves a reservoir in the bottom of the pot, for the plant to obtain water etc., continuously. This pot can be put in a hanger. Using a large pot with holes in the base, I attach a saucer to the pot, as the pot just fits inside the saucer, I attach with two fine wires, it becomes the reservoir, and I do this for hanging purposes. As per photo. I give plants a good flush-out every two weeks. When I Fungicide or Insecticide, I flush out 2/3 days after they are applied, as with most, their usefulness has passed. I do not use clear pots, as with added moisture in the pot, it causes algae. When repotting an orchid which is going into expanded clay balls, with a reservoir, remove ALL DEAD and BADLY DAMAGED ROOTS. If left, they cause a mush wet area. This should be done with all plants when repotting. Expanded Clay balls may be reused if all material is removed and they are soaked in TRISODIUM PHOSPHATE for 2 hours. They then need to be rinsed, then soaked for 1 hour and rinsed again.

three plants in balls

  Plant in pots with reservoirs

(From Left to Right)

Standard Pot with Saucer

Pot with holes in side

Pot with attached Saucer 


Sizes available:

8mm-16mm……….16mm……….30 Elongated ………..30mm

three sizes balls


  These balls are available in 50 litre bags.  




The balls are very light and plants will need support, until they are well established. To balance the pot, I put some stones in the bottom of the pot.

If you water with force, you can blow the balls out of the pot. Put some small pebbles on the top to prevent this.

The price is comparable to other potting materials. One big advantage is the ease to clean and reuse, after sterilizing. (Trisodium Phosphate)

Because they are round, there is very little chance of the airways becoming blocked, good ventilation and passage-ways for the root system. Good humidity around the root system, which also flows through to the plant, helping to keep it cool and stop dehydrating.

To start using the expanded clay balls, use them in a standard pot and treat them the same as ordinary potting material. If you are successful this way, then try using the reservoir, preferable no deeper than 10mm. in only clay balls.


three months no reservoir

The plants in pots with a reservoir tend to not dehydrate as much. I watered some plants in just pots every day and found they also held their shape.

The roots and new growths do very well, they are quick growing. Some plants have flowered since being repotted; the flowers were up to what you would expect after being repotted. When the plants are established, the flowers improve in substance and colour.

If you live where the winter temperature drops to near zero or lower and you are using a saucer for a reservoir, remove saucer and grow as normal during the cold. If you have a hot house then you can grow with reservoir. If you are growing with a fixed reservoir, you will need to grow them where the temperature is above 8/10 degrees minimum. Too cold can damage the root system, where the reservoir is concerned.

Expanded Clay Balls are available from:

(02) 96687977




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