Perlite

Premium Perlite supplies – 2L 6L and 20 L

Quality Perlite available with WaterUps Orders

 

Adding perlite to the wicks of any WaterUps cell is recommended as a key element in increasing wicking efficiency and creating optimal soil aeration in any garden bed.

Perlite is an extremely lightweight stone-like material, typically white in colour. Its original form is dark Perlite Ore that is heated to over 1000°C and in the process expands to many times its original size. At that point, perlite becomes extremely porous and highly absorbent, making it the perfect medium for soaking up water, or in our case wicking up water.

The wicks are the four feet at the base of each WaterUps cell. With our system, you only need to fill up these wicks to draw up water from the reservoir that the feet sit in. 

 

As such, our wicking technology advances sustainability in two ways:

  • It uses polypropylene, a strong, inert recycled plastic to create a waterproof water reservoir under the soil
  • Gardeners only need to put Perlite in the feet of the WaterUps Cell – not the whole base of the reservoir – to draw up the water that is in the reservoir. The wicking will continue to work as the reservoir water level drops and the water reservoir will only need to be topped up when it’s very low.

You need only 2 L of Perlite to fill the four feet of one WaterUps cell. 

 

Perlite Packages

We sell Perlite in 2L, 6L and 20L bags to anyone purchasing a WaterUps system. The calculator tool can help you work out how much perlite you will need for your custom garden bed requirements,

Safest Wicking Medium 

Our Perlite is sourced from an Australian leader in premium perlite manufacturing. It has received Organic Certification from ACO Certification Ltd, Australia’s largest certifier for Organic and Biodynamic products certified to Australian and International standards. It’s a pure organic product certified for growing safe, high quality and nutritionally valuable foods. It’s also safe around animals. It will not break down or rot like some other growing media like coconut husks or coffee beans. Perlite is sterile, pH neutral and natural (as opposed to polystyrene).

Perlite, Sand or Scoria?

Understand why Perlite is best.

In the process of developing the WaterUps Wicking system we evaluated several alternative wicking mediums, including sand, gravel, scoria and perlite, and reservoir construction methods before settling on the WaterUps Wicking plastic cell structure with perlite.

Here’s what we found with river sand, gravel, and scoria – which in the past have been used as a fill or bottom layer to a wicking reservoir and as a wicking medium.

To make a reservoir, a support structure must keep the water and the soil apart. Soil permanently sitting below the water line will quickly go anaerobic and give off an offensive smell. Traditionally, this has been done by filling the reservoir with a mineral compound, being sand, stone or scoria covered in a layer of geotextile fabric to stop the soil shifting down and mixing.

Sand has the greatest wicking potential due to the small gaps between each grain allowing capillary rise to work most efficiently. Sand also displaces the greatest amount of volume, around 85%, holding only 150mil of water per litre of sand, therefore allowing the least amount of water holding in the reservoir.

Stone or gravel is the worst performing mineral to use in a wicking reservoir. Due to the large gaps between each particle, capillary rise is very ineffective, and may not work at all as the reservoir drains. Solid stone also displaces a large volume, about 55%, holding 550mils of water for each litre of stone, leaving the reservoir holding just more than half available water. Blue metal, a very common aggregate, has a pH of 8 or higher, causing many soil and plant problems. Other aggregates misused in wicking reservoirs are recycled aggregates that can have pH readings of 11.5 or higher.

Scoria is the most common aggregate used to support the reservoir of a wicking bed. Scoria displaces around 45%, leaving, in comparison a good performing mineral fill, holding 65% of it’s volume as water, or 650mils for every litre. It is a volcanic rock that forms from basaltic magma that is very porous, therefore has great wicking potential. However, scoria contains 50% silica and 10% calcium, with many other trace elements. Such a high percentage of calcium will have a profound and long-term effect on pH.

Perlite is sterile, pH neutral and natural, holding around 55% of its volume as water. For 1lt of perlite 550mils of water can be added to the container before exceeding 1lt. Due to the inert nature of perlite and consistent grain size, it was chosen to go in the feet of the cell to wicking water from the reservoir.

The WaterUps wicking cell has 4 feet that support the tile and contribute to 12% of the volume of the reservoir. These feet act as the wicks in the WaterUps system. When the 4 feet are filled with 2lt of perlite that can hold 1.1lt of water, the overall net displacement is 900mils, leaving a total 16.4lt of water available under each cell. 16.4 is 93.7% of 17.5, making the WaterUps wicking cell the most effective and efficient.

What does it matter? If a reservoir volume was 100lt, that will measure 1m x 1m x 10cm deep.

  • Filled with sand, would hold 15lt of water (1.5 watering cans),
  • Filled with stone, 55lt of water (6 watering cans).
  • Filled with scoria, 65lt of water (7 and a bit watering cans).
  • Not filled, but supported by WaterUps wicking cells, will hold 93.7lt of water (over 10 watering cans, so we suggest you go get the hose).

The amount of water a reservoir can hold will determine the number of days between refilling.

Even if you can look past the inefficiency due to displacement and any potential chemical imbalances that could occur using some traditional wicking materials, there is still the fact that these minerals are mined and transported. By using a recycled plastic, WaterUps is putting less in, and taking less from the ground.

Both river sand and scoria are less environmentally friendly from a mining perspective.