donderdag 19 december 2019

De Wormenhotels van Amsterdam West

130 jaar oude Plataan op het
WG Terrein in Amsterdam West. 


4 nieuwe wormenhotels in Amsterdam West voor buurtcompost initiatieven. 




West Begroot.


In Amsterdam West wordt ieder jaar een budget beschikbaar gesteld voor bewoners initiatieven. Dit budget wordt verdeeld door de bewoners van West die hun stem uitbrengen op ingediende projecten. 

WºRM Basiq in de Lanseloetstraat in A'dam West. 
Zo werd ook het afgelopen jaar het plan ingediend door een bewoner om meer wormenhotels te plaatsen in Amsterdam West. Het plan kreeg genoeg stemmen en vervolgens werd Compostier gevraagd om 4 nieuwe wormenhotels te plaatsen op locaties waar bewoners al eerder aangegeven hadden een wormenhotel te willen gebruiken. 

De gemeente Amsterdam heeft zelf een wormenhotel laten ontwerpen naar aanleiding van het succes met de wormenhotels die Compostier eerder maakte voor de gemeente voor buurtcompost projecten. 

Ragna Horn (Projectleider Zelfbeheer/ Groen in de Buurt - Gemeente Amsterdam) verkoos de wormenhotels van Compostier over 'het gemeente model' omdat deze meer robuust zijn en praktischer in gebruik. En vandaag konden de eerste drie op hun nieuwe locatie geplaatst worden. 


Bewoners willen composteren


Er zijn steeds meer groepen inwoners van Amsterdam (en natuurlijk ook in andere steden in het land) die niet langer hun groenafval willen meegeven met het restafval. En zo groeit het enthousiasme voor de wormenhotels in de stad.
De staf van De Gibraltar Speeltuin
inspecteert het nieuwe wormenhotel. 

In een Compostier wormenhotel wordt een bodem aangebracht van koolstofrijkmateriaal, waarop reeds veel microben leven (houtsnippers en herfstbladeren). Deze bodem zorgt voor een goede start van het composteren.
De bodem neemt tevens het vocht op, dat vrij komt bij het composteren.

De groepen buurtcomposteerders leren in een workshop hoe ze het wormenhotel het beste kunnen gebruiken en worden aan de hand gevolgd. Tijdens de opstart fase gaat het ecosysteem door verschillende 'groei-momenten' heen, waarna de levende massa in het wormenhotel stabiel wordt.

Wanneer het wormenhotel goed gebruikt wordt kan er een grote hoeveelheid groenafval verwerkt worden tot rijke wormencompost.

Na een periode van 6 tot 8 maanden kan de eerste compost geoogst worden en verdeeld worden onder de buren, of gedeeld worden met een groen project in de buurt.



Wormenhotel en Rolstoelschommel bij speeltuin
De Gibraltar. 





WºRM11 bij het WG Terrein. 

Klein dorp in de stad


Sommige bewoners van het Willemina Gasthuis Terrein (WG Terrein) wonen reeds meer dan 30 jaar op deze unieke locatie in het drukke stadscentrum. Tussen de drukke Overtoom en de Kinkerstraat in ligt deze oase van rust. Met enkele bomen die over de honderd jaar oud zijn en een pleintje waar je even van de stilte kunt genieten. 

De bewoners wilden al langere tijd een wormenhotel en nu dankzij West Begroot kon een eerste wormenhotel geplaatst worden bij het oude ziekenhuis. 

De groep bewoners van het wg terrein beginnen met dit kleinere wormenhotel. Wanneer het project een succes is, wordt gekeken of er meer wormenhotels in dit kleine stadsdorp geplaatst kunnen worden. 




Ongedierte in het wormenhotel.


Reeds sinds 5 jaar is Compostier aan het experimenteren met het bouwen van wormenhotels. Het eerste wormenhotel voor een buurtcompost project werd gebouwd in 2014 voor de Frans Halsstraat. Sindsdien zijn er vele wormenhotels gebouwd, steeds een beetje beter, met de ervaring en feedback van gebruikers om van te leren. 

Het is een enkele keer gebeurd dat ook in de Compostier wormenhotels een ongewenste gast werd ontdekt. Een enkele keer waren de kieren tussen het hout te groot geworden door het werken van vers hout (hout van bomen uit de stad gezaagd bij Stichting Stadshout), een andere keer doordat een gebruiker het wormenhotel vergeten was te sluiten. In alle gevallen hebben we deze ervaringen kunnen gebruiken om er voor te zorgen dat er geen ratten in het wormenhotel kunnen komen. 






Nieuwe serie wormenhotels van Compostier. Boven: de WºRM11 (links: uitvoering met gerecyceld kunststof en gerecyclede hardhouten vlonder planken gekregen van De Dakdokters + rechts: standaard uitvoering in Douglas hout). Onder:  de WºRM Basiq,




VvE plaatst wormenhotel in Amsterdam Noord. 


De gemeente maakt veel van deze buurtcompost projecten mogelijk. Met subsidie en fondsen voor projecten die helpen de stad te vergroenen. Maar er zijn ook inwoners van Amsterdam die zelf investeren in een wormenhotel voor eigen gebruik en zo zelf verantwoordelijkheid nemen om hun eigen groenafval te verwerken. 

Zo komt er nu aan de Meeuwenlaan in Amsterdam Noord. 6 huishoudens gaan samen compost maken voor de gedeelde moestuin. Super leuk! En we hopen dan ook dat meer VvE's volgen.
Want er gaat nog altijd te veel groen verloren!


Heeft U ook interesse in een wormenhotel voor uw eigen VvE, woongemeenschap, woongroep of appartementencomplex? Stuur ons dan een email !




zaterdag 7 december 2019

Rooftop Composting using the WºRM31_low Worm Hotel


Vermi Composting at a Great Height. 


View from the 30th floor at the office building of
Nauta Dutilh at the center of Rotterdam

Rooftop Worm Hotel at the Office.

Worm Hotel at Fluor - Hoofddorp
Especially for the office of international law firm Nauta Dutilh at Rotterdam and the office of global engineering and construction company Fluor at Hoofddorp we designed the WºRM31_low. 

The WºRM31_low.

Is a worm hotel with 1400 Liters of composting capacity that can be placed at rooftop terraces. To be able to compost a vast amount of green waste at the rooftop terraces of both office buildings, we had to distribute the total weight over a larger surface. 

The internal height of the composting chamber is reduced, but by creating a larger surface inside, the amount of green waste that can be composted in the worm hotel is not reduced. 

This worm hotel is designed as a Continuous Flow System (CFS).




Garden on top of the worm hotel with light weight substrates.

The worm hotel designs of Compostier all have a garden over the full surface of the furniture. In this way the worm hotel is adding green space to any location where it is placed. The garden boxes can be used to grow edible herbs to use in the kitchen or for herbal teas. 

To minimise the total weight of the worm hotel we are choosing special substrates designed for a green roof. These substrates allow for waterretention without adding too much weight to the total weight of the furniture. 

One of the substrate we use is FytoCell from Resins Agro

The environmentally friendly foam-like material can absorb 60% water of its own volume. The weight is substantially less then normal rooftop substrates: 1000 L of the FytoCell only weighs 60 kg. The foam can be used as a hydroculture, but we mixed it in with other rooftop substrates and covered it with a thin layer of substrate and coco husks. The coco husks cover helps to avoid evaporation of the moisture in the garden boxes. 

To avoid that rainwater fills up the garden boxes each garden box has an overflow. 

The WºRM31_low at the rooftop terrace of Fluor.
In the background you can see the HRBS table
with fresh & locally grown herbs for herbal teas. 



Modiwood® A sustainable alternative for hardwood. 

For the worm hotel of Nauta Dutilh at Rotterdam we chose ModiWood as a material for the outside of the furniture. ModiWood is thermally modified pinewood. The treatment gives the pinewood a good outdoor resistance and makes it possible to use it outdoors without the use of paint or other chemical treatments. 

Another advantage of using ModiWood is the weight of the material. ModiWood is much lighter than hardwood.


WºRM31_low at the workshop at the HEMbrugterrein at Zaandam.
This model was made using ModiwWood. 


The Compostier Worm Hotel - a natural system solution for local & circular use of green waste.

We designed the worm hotel to introduce a non-tech & natural solution for green waste. The furniture uses only natural systems to break down the organic material into a rich fertiliser for the soil. By studying and learning from nature we were able to design a vermicomposter that is durable, practical & looks great, but most of all produces the most wonderful & alive soil. 



Woodchips & cardboard as a basis in the worm hotel. 

Autumn leaves as a bedding & cover material.



Its been a great year! 


Over the past year we have been able to realise many great projects. We want to thank everyone that supported us. Best wishes to all and a great start of the new year!



We wish you a Merry Christmas & a Green 2020! 






zondag 4 augustus 2019

The WºRM: A home for nature in the city



Worm Hotel near Amsterdam Central Station used by Grandcafe 1884

Natural life in the Worm Hotel. 

Inside the Worm Hotel ('Wormenhotel' in Dutch) something wonderful happens. Millions of organisms life together and transform what we consider as waste into healthy new soil: living soil. The leftovers from vegetables, fruit and other plant based materials are broken down and turned into humus.

In the worm hotel is room for many organisms. Composting worms play an important role, adding fertility to the compost with their 'wormenpoep' (vermi castings) that is full of beneficial micro organisms. The worms feed on the micro organisms and actually breed them inside their bodies. After digesting organic material containing micro organisms and excreting the castings the colony of bacteria and fungi will increase since the worms breed more then they digest.

Worms give their name to the worm hotel, but they certainly don't life in it on their own.

Woodlice (Pissebedden in Dutch) are also a common resident in the worm hotel. Woodlice are very important for the breaking down of dead wood and other organic material. Another benefit of woodlice in the worm hotel is that they change their skins when they grow. The woodlice have an exoskeleton. This hard shell does not grow when the animal grows so they have to change into a new skin when growing. The old shell is left behind and is broken down in the composting material.
Exoskeletons of insects and woodlice contain chitin. This compound can only be broken down by specific enzymes. The worms contain these enzymes in their digestive tract and increase the production of this enzyme when the digested material contains chitin. This enzyme will also be excreted with the worm castings.
I have been told that, when using vermicompost containing this enzyme it will make plants more resistent to attacks of plant eating insects. The plant will 'taste' of the enzyme and insects will leave the plants alone. If this is true I am not sure, I have not found a research yet stating this, but I am very curious about trying it out. In any case it sounds applaudable to me.

Foto Getty Images/ Istock photo.


Fruit flies are also a common (but less welcomed) guest in the worm hotels. When their numbers get too big, they can be quite a nuisance. However, they are also composting agents and help transform organic material into rich soil. The key is to look for a balance in moisture and feeding speed (amount of foodwaste fed to the worm hotel), to keep the population of fruit flies in check.

Spiders will join the worm hotel family at some point and will hunt on the flies and other small organisms. They play a role in keeping organisms in check.

Mites are small to very small organisms that also play an important role in the soil. In the worm hotel different kinds of mites can be found. The mites feed themselves with organic material, with springtales, larvae of insects or other mites and some even eat worms. The mites are important for healthy soil.

Springtail larvae.


Springtales are among the oldest animals around us. They can be found by the thousands in a square meter of soil. The larvae of springtales are a common resident and can easily be seen in the worm hotel. They are white oval shaped animals. Springtales digest organic material and help to create humus.

Ants are living on our planet in huge numbers. In number and even in total mass they outnumber us humans. Ants are helping your garden by cleaning it from dead organic matter and insects. But they can take over the worm hotel if they find it a cozy home. In general you do not wish for ants to nest in the worm hotel, and if you find a nest it might be a good idea to mix things around. I have not found proof that the ants harm the worms, but I can imagine they don't allow worms (and other organisms) in their nests and if the nest grows big there will be less space inside the worm hotel for the other residents.

There are many other organisms that can be found in the worm hotel and I belief that the more complex the eco-system is, the more alive the soil will be that is created.


Unbalanced system.

Whenever one organism finds an environment in which it can thrive it will florish. And this can result in a 'plague'.

For instance the fruit flies we mentioned earlier can multiply in such numbers that you are welcomed by clouds of flies that leave when the worm hotel is opened. Only to return to the inside of the furniture after some time.

Window in the worm hotel.


When your worm hotel eco system seems to be out of balance it helps to stop feeding the worm hotel for some time and add extra dry bedding material on top and nature do its tricks to rebalance the system. For instance, when too many fruit flies are in the worm hotel, there will be big numbers of fruit fly larvae. Organisms that feed on the larvae will start to grow in population and bring the number of fruit flies down.

We humans tend to look at 'a problem' and look for 'a solution' to 'fix it'. When we understand there is not one problem, but that it is part of a changing process with many players involved that work together (or against each other) to create a balanced eco-system, we can build understanding and appreciation for this process and use it to our mutual benefit.

I belief it is important that we learn again to life with nature and allow these moments of unbalance to occur for the eco system to grow stronger and more complex. It will imply that we ourselves will encounter some discomfort some moments and need to observe and learn what needs to be done to help the system to be more balanced. We need to work with nature, not against it, if we want to re-establish a more healthy way of living on this planet.


Still from our crowdfunding film from 2018.

Human nature

If you are reading this article my guess is that you consider yourself a human beeing. One single organism of the species Homo Sapiens. But if you look at yourself closely you will find that your body exists of many (uncountable) cells and organisms that have decide to work together and 'be' your body together. So already on an 'individual' level you are part of an eco-system. 

In the human world we tend to look at our environment for our own advantage or for things we need to protect ourselves from. Even now in a time of 'climate change' and potential world wide catastrophe the general concern is what 'harm' could happen to 'me' and 'us'. 

I belief that when we understand we are not apart from our environment, but that all is connected, and at some level really is all one, that we can start to make better choices then the selfish ones we make now. We need to care for all, as if it is for ourselves. 

That means giving space in our midst to plants and animals. Even if we think they are not profitable or directly beneficial to us. They are part of the whole and just as important. 

Words as 'plaque' or 'pests' and 'pest control' are words we need to abandon. Just as words like 'waste' and 'waste management' they hold us in a mindset that keeps us apart from our true nature. 



Worm hotel projects help reconnect with nature in the city.

I started designing worm hotels in 2012 because I wanted to learn myself about the natural cycles and help re-establish the connection with nature in the city. I am still learning and feel grateful for all the support I have been given by people all around the globe. 

At this moment I am looking for ways to share the experience I have been able to collect so more people can start using worm hotels and learn about healthy soil in the city. 

Over the past year I have been placing a number of worm hotels at restaurants and offices. It is great to see that also amongst food professionals the interest in reconnecting with nature is growing. 

Right now I am in Oslo start a first worm hotel pilot here in Norway together with Nabolagshager Oslo

If you like to learn about our worm hotels and see possibilities to start a project in your own town, please feel free to write us at: info@compostier.nl


Worm hotel in use by the office of Google Amsterdam.

Kitchenstaff from Google's office is happy to meet the new residents.

Our workshop at the KasKantine in Amsterdam.
On the front: wood from StadsHout Amsterdam.

Children take a look inside the worm hotel in The Hague.

Chef Rick from Restaurant As is using self made vermi compost
in the garden of As.