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Questions about what Sideau® is made of
  • Sideau® is made of Earthwool®, a natural product made from basalt, a volcanic igneous rock. In addition, Sideau® is made with Ecose®, a natural binder, free from acetylates and formaldehyde’s. In the composition of the binder, therefore, petrochemical raw materials make way for vegetable raw materials like sugar beet or cane sugar. By heating, the material caramelizes hence the brown color. During the production of Earthwool® , seventy percent less energy is required than in the production of traditional yellow rockwool. Sideau® is noticeably softer but still very dense, does not emit any odor or discoloration in the water. Sideau® is therefore friendly to people and the environment. It does not crumble and is therefore pleasant to process.
  • Sideau® is made of 97 % Basalt (a volcanic rock) and 3% bio-based binder (Sucrose).

The Basalt is heated to an extremely high temperature so that it melts, and the liquid rock is then spun into fibers. Depending on the density we want per product, a number of layers are placed on each other and then pressed together. This also explains the ribbed top. After this it is cut into the different product shapes and packaged.

  • It’s mined within 100 km of the factory and then transported by truck.
  • We source the product materials from Europe.
  • The rock is heated to 1300  ̊C by coal. The Earthwool® is cured at 600 ̊C by heating it with natural gas.
  • No significant use of water or other natural resources.
  • Some iron ore is found in the volcanic rock which is recycled in an iron foundry.
  • All the additives are 100% natural . No chemical resources or products are used.
  • The accessible rock reserves of basalt, anorthosite and carbonates are large enough to supply current human demands for millions of years and can be regarded as inexhaustible resources.*
  • The natural production of carbonate and basalt even overwhelms the consumption in stone wool production. These resources are renewable in the geological sense and can even be regarded as sustainable resources, unless other human activities target these resources.*


* Source: T.W. Dahl: The human impact on natural rock reserves using basalt, anorthosite, and carbonates as raw materials in insulation products published in International Geology Review 53(8):894-904 2011.

  • Basalt is volcanic rock. Basalt sand or basalt flower is what is left of Sideau® when fully degraded.
  • Basalt sand (flour) is specially intended for changing and improving for example heavy clay soil.
  • The young volcanic basaltic rock (which, unlike lava flour, is not ground and therefore has a harder structure) contains silicon, trace elements and minerals.
  • Basalt flour is used for improving clay soil and contains silicon, trace elements and minerals. This not only makes heavy clay soil easier to work with but plants also flourish on it because the cell wall is strengthened, it stimulates growth and bulb plants are given the opportunity to root deeper.
  • Another advantage of using basalt sand or flour is that nitrogen is captured.
  • Many growers use this natural product to strengthen the natural resistance of crops. With the aim of combatting pests and diseases.
  • It’s exactly the same material. We initially used “floral foam” in the name to make it recognizable to the customers. But because we do not use petrochemical (plastic) materials and our products are therefore not foam, we want to have the name free of foam. Sideau® is now the new name for the material in any form.
  • Our products are completely natural and therefore not harmful to the environment.
  • For every kind of flower (silk, fresh or dry) and plant. Also as a growth medium.
  • It can be used both dry and wet for all flowers and plants.
  • The material can be made wet again and will also retain the added water.
  • Yes Sideau® is 100% natural.
  • Of Sideau® only basalt flour remains over time and circumstances and that is a 100% natural product.
  • Basalt flour is used for improving clay soil and contains silicon, trace elements and minerals. This not only makes heavy clay soil easier to work with but plants also flourish on it because the cell wall is strengthened, it stimulates growth and bulb plants are given the opportunity to root deeper.
  • Another advantage of using basalt flour is that nitrogen is captured. Many growers use this natural product to strengthen the natural resistance of the crop. It keeps pests and diseases at a distance.
  • The basalt flour is easy to spread over a crop. It is advisable to spray with water so that the basalt flour is thoroughly mixed with the clay soil.
  • Depending on national regulations, Sideau® may simply be disposed with organic waste.
  • When you have leftover pieces after cutting Sideau® to size or if you remove the flowers after use, you can cut the blocks or pieces into small flakes and then use them as a substitute (substrate) of soil in your flowerpot, planter etc.
  • A Sideau® block of 23X10X7.5 cm absorbs water in 15 seconds and then holds it well.
  • You don’t have to leave Sideau® in the water for more than those 15 seconds.
  • Sideau® is very easy to cut into any shape with a rock wool knife or for instance a bread knife.
  • There is a small EC increase (EC 0.8) due to Ecose®
  • Sideau® blocks are Ph neutral (Ph 7.3).
  • Almost nothing crumbles or breaks off the Sideau® blocks when cut.
  • Sideau® holds the flower stalk firmly in the block and you can also put the flower stem in again. Clamp well in the pot or vase due to the resilience.
  • In contrast to floral foam, that is made from oil derivatives and phenol resin – which is plastic – Sideau® is fully biodegradable. Therefore Sideau® is perfectly suited for florists and flower arrangers who want to use an fully environmental friendly base for their creations.
  • It takes up to roughly 15 seconds to fully saturate a 23X10X7.5 cm block of Sideau®.
  • Yes, you can easily cut Sideau® We suggest using a serrated knife.
  • As with other floral media, the skills of the designer is important to the stability of the structure. The surface of the product does not “heal” or close if a stem is inserted and then removed. But the Sideau® material is spongy so you can stab a stem again.
  • The ribbed top is slightly harder than the side of our material. Therefore, with softer stems, you may first have to stich a hole. Or you use the side of the material (the layered side) that is softer. If the material is wet it will also be easier to use.
  • You can reuse it as a design medium, though the product will begin to fall apart as inserted stems create permanent holes. Some arrangers reuse the material by tying chicken wire around it. Sideau® will absorb water again.
  • Sideau® leftovers are perfectly reusable for growing plants from cuttings and seeds when cut or tore into little pieces.
  • As Sideau® has a high draining level, we don’t recommend using it for hanging floral designs. Sideau® performs best in a container. If you use Sideau® without a container, be prepared for water drainage.
  • The drainage will be high in a vertical position. If the flower stems are not fully inserted, the flower life will suffer. Using the block in a horizontal position will result in the best performance. You can pour or spray water over the block over and over again. Sideau® continues to absorb water.
  • If there is demand for other shapes and sizes, we will expand the range to suit market demands.
  • We advise storing it in a dry environment.
  • Metal pins do not work well with Sideau®. However you can try bamboo mossing pins and cardholders. They do perform well.
  • Yes, Sideau® works great for arranging both fresh cut and dry flowers. We have conducted numerous extensive tests of Sideau® in our research labs to evaluate physical properties and effects on flower life. Here are some of the things we learned.
    • Shows low foliage toxicity and leaf yellowing
    • Has fast saturation and a high water holding capacity
    • Will not result in “colored water”
  • Sideau® is completely Natural
  • Sideau® is 100% degradable until basalt flour remains
  • Sideau® gives no water coloration
  • Sideau® gives no waste because you can reuse pieces as a substitute for earth
  • Sideau® is expremely user-friendly
  • Sideau® is easy to cut into any shape
  • No microplastics are left behind because Sideau® is a 100% natural product
  • Sideau® can be used for all flowers or plants
  • We have conducted numerous tests in our research labs and have found Sideau® to be safe for flowers. Flower life, stem burn, and leaf yellowing test results all fall within a range we deem acceptable. As we suggest with all floral media, saturate Sideau® with a solution made of water and a kind of Flower Nutrient.
  • Sideau® is 100% biodegradable and compostable under conditions such as cold, heat, wet, dry, the material decays slowly. What remains is Basalt sand. This is a natural product that is also used in agriculture and horticulture to, for example, upgrade heavy clay soil. There are a lot of minerals in Basalt. It is not advised to throw a block in its current form in your garden.
  • Shredding or tearing or cutting into pieces speeds up the process. Pouring boiling hot water over it also helps, because then the sugar binder dissolves and the material breaks up faster.
  • Throwing the material into your waste container depends on the laws and regulations in your country.
  • If you do not reuse Sideau®, you may deposit it in small numbers in the green container (end user) depending on the legislation of your country. Not in large industrial quantities.
  • Sideau® may even be shredded together with the flowers and deposited with the compost. This is done, for example, at natural cemeteries.
  • No Sideau® doesn’t irritate. Only people with very sensitive skin can experience slight skin irritation. The irritation warning has to be included on the labels due to international law.
  • You should only wear protective clothing if you cut, saw and process Sideau® in large industrial numbers. Then the room also must be ventilated.
  • In normal use, no dust will be released, but as with any product that creates dust particles, if you are generating high concentrations of dust in a confined space, wearing a face mask is recommended. Dust does not occur with wet use. For more information, refer to the Safety Data Sheet (SDS).
  • If you have a very sensitive skin, you may experience a slight skin irritation when using Sideau®. In this occurs, wearing gloves and washing hands after using Sideau® are recommended. Skin irritation does not occur with wet use. For more information, refer to the Safety Data Sheet (SDS).
  • Agra: We are originally a producer of natural mineral rock wool products for agriculture and horticulture. Agricultural is in Dutch “Agrarisch” Wool: Because we produce everything from natural mineral rock wool.
  • The product name Sideau® is derived from the first name of the owner of Agra Wool, which is Sido. Furthermore the name consists of two phrases: Si and d’Eau, which explains one of the main characteristics of the product: it absorbs and holds water perfectly. Even better than the traditional floral foam. So, yes, water!
  • Unfortunately, that is not possible. However, you may purchase a single block, which allows you to trial the product without committing yourself to a carton of 20 blocks. You can also check our website ( among distributors to see if there is a distributor near you. They might be able to provide you with a sample.
  • We have since April 2021 the approval of SMK to be added to the list of products that may be used for florists with the label “Barometer Duurzame Bloemist” (Sustainable Florist).
  • SMK is the research institute that determines which products meet the requirements of the “Barometer Duurzame Bloemist” (Sustainable Florist).
  • Also RHS in the UK has approved our floral products as an alternative to the regular petrochemical floral foam blocks of other brands.
  • We have investigated the viability of achieving a claim of compostable or biodegradable, and for now it is not possible with this product. The reason for this is that it does not completely dissolve, but Basalt sand remains. Although basalt sand is 100% natural and consists of 97% Basalt and 3 % Organic binder (sucrose). Compare it to cultivation or potting soil. We are still working on a few tests in laboratories and hope to get a quick conclusion and a quality mark.
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Sideau is affiliated with the Barometer Duurzame Bloemist (Sustainable Florist) initiative 

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