today we have finished the cccb tool here in tarragona.

we started some weeks ago preparing the materials, having workshops about composting and cartography all the local sources of organic left overs. we are lucky in this project cause we already have a restaurant (taula amiga’s cantine) that prepare meals to around 40 families. we also located 4 vegetable stores near the farm and of course we have the left overs of all the participants of this project. now let’s make compost!! :)


day#4 workshop @ iaac

today some of IaaC students went for some short vacations so we went to visit a place they already know. valldaura.


we went walking from mundet metro station. ~1h climbing collserola park

valldaura walking path

we were welcomed with open harms and dirty hands by nuria ;)

after a short visit to the main building, green fab lab, woodshop, the kitchen and the property we started the preparation of one of the most important tools for a urban farmer. well for every urban , I would say, since you can include here cats and gods :p the bokashi system.

first we need to make a starch base. we used rice and shake it with water. 1 clean jam glass + ⅓ of rice +⅓ of water + ⅓ of air. shake it, take the rice. leave the jam glass lousy closed (must breath) for 15 days in a dark, ventilated and fresh place.

bokashi step1

we were supposed to cook the rice, but since silvia was already cooking for some workers we were invited to join the same table :) a great pasta with ginger!! we here also eating an omolette so we gave our rice to the chicken :p

next week we have holidays. the right time to let the rice milk work for us ;)


amazing composter mixer

I love this moments when you find something brilliant, low budget and low tech :D

check this out! is a old spring from a truck and it’s used to aerate the composter. you give some turns, raise a bit so that air enters in the midle of the layers. remove by turning conter clock. you make this in 4 diferent spots and your composter will have a oxigen boost ;)

IMG_2679 - 2012-05-13 at 11-42-54

IMG_2681 - 2012-05-13 at 11-43-06

recover materials from abandoned factories




ooooo men… almost didn’t sleep today.. thinking the million things that were on that abandon factory, in the quality control lab, on the storage that feed all the departments of this polimer/metal factory.

but also took my sleep the huge environmental disaster that happens day after day with all those tones/liters of chemical products that are spilling drop after drop the the river. your tears fall apart when you see a 200L of viscosity just covering the “danger for the environment ” label. didn’t took my camera with me so you just have to believe that this place exists and you can be certain that the same is happening in all the post industrial cities. how can we revert this? how long it will take? how can we, refarm, contribute to monitor and implement systems that not only contributes to the “cleaning” but also make visible what is happening on a ecosystem that by chance you are part of it.

mojitos re:farm

this was one of our best sellers :) the mojitos re:farm.

first appearance here in tarragona during ciutatscreactives.

a resume of the building process:

mojitos 3

we got the structure from cal pobre. It belongs to the local scouts :)

mojitos 2

we then made the mint pots. a mix of hydroponics and capillarity .

mojitos 1

build the structure to hold all of the tools, pots, hold a cutting table, secrete spots to keep money, towels, refills and white rum :)

mojitos 4 1

during the day workshops and fresh mint tea. during the night mojitos and real party-crowdfunding ;)

mojitos 4 2

what a great learning and funding tool! thanks all for the contributions:)

we now must attach this with our electronics.. humm this could be funny.. gps.. twitter.. the summer is coming.. humm

who wanna join this project? come on, send me a email and we make a europe tour this summer lol

pressure switch communication

So it definetly works!!!  My depest repect to you Mr. Medici. Your self automated watering sytem is the best low budget automated watering sytem and it beats all comercial products. 10 John Meda simplicity points for your design. I definitely fall in love with it :).

What i have seen is that it took nearly 49 houres for the plant to consume sufficent water and to overcome the hight distance between pressureswitch and ceramic sensor to do the switch.

To do the reverse operation it took nearly 50 min or to be less precise 1 hour. I handwatered the plant with about 400ml of water , directly , no dripping system. Thats the next point about this system. If it is indoor it must be precise , otherwise you water your carpet too. This will be relationated with the tubes-diameter, folds and switches inside the system, the kind of valve and pressureswitch, the waterpressure, the hight of the watertank etc.. But it is not a real problem you can addjust all this parameters with the height of the pressureswitch.

mange bien :)

Till i find out how the wiring is done for the pressure switches i decided to make a little test about the response time of the system. What i want to find out now is,  do that really works at my place with my parts and how much time my plant needs to drink the water from the switch and does it  switches. If this is done I will water the plant by hand and i will see if the process will be reversed and the switch will go back in his OFF state.

The plant is a present from a friend of us and I have no idea what typ it is, but I very happy with it and sometimes when I’m out I give here a place next to the window to enjoy the day. I watered that plant  in summer at here house and it is a very thirsty type. In a previous posting about the ceramic sensor i found out that the plant consumes about 15 ml in 24h. ( proberly, I  didn’t measured they water amount , because i dont have that equipment ).

I filled the switch and the sensor with water , and it is imposible ( with my tubes etc… ) that you dont have air in the system, but i  think that that will not be a problem. So i filled everything. The switch made click. It just takes a little amount of water, my tubes are very small, so i think the system is quite responsive.

I checked they continuity at my ports and they measuring gave me the values:

Filled = switch OFF = pin 21 + 23  =  000 /   pin 21 + 22 = 1

so during the next 24 h they continuity should change if they plant drinks the water from the switch.( yummy )

What I forther  did was to water the plant a little around the sensor. As you can see in the foto the water passed the earth and a little stayed in the groundplate. What I have seen then is that the earth absorbed that water during one hour into the system and that made the bubbles in the tube move down( 2 cm) . So it looks like that he system is really good responsive :). One point more , the switch is 40 cm under the flower pot, that is importend , because the system and the pressure relates to the difference in height from the sensor to the switch.

pressure switches / pressostate

The 2 differnt types i bought and i have no idea how they really work, but with the help of the internet I found out that one of them is  from a dishwasher and not from a washing machine. With a multimeter I made a continuity tests and it looks like that one is having 1 trip points and the other is having 2 trip points.

With the contiuty test you can test the pins how they respond and if the work.  You just have to measure two  pins and them blow into the switch, if the switch works you hear a click from the switch and the continuity will change from 1 to a 3 digit number and vice verce. Those pins will later be connected to the solenoid valve or water pump and send the signal to water our plants :)

Here is small video that explains pressure switches.
youtube pressure switch video

we got a lab

F.. long time that we’ve been struggling to have it and now we were invited to use it as much as we can :D

refarm the city project was invited to participate on the development of ecoLAB, an initiative of plantaformacero born at LABoral art center of gijon. it’s a one year collaborative project were we are going to develop some tools for urban farmers. but the best part is that we will not be alone :) great guests were invited: andy gracie, susanna tesconi, the guys from zoohaus, cova dos ratos, our friends maki, rubén and other collectives from spain.

here is our canvas

we will dedicate a page to these developments, go and check it :)

waste or food

by traveling from city to city I find different sources of the stuff I need, different ways to get to them and big differences on how its each city manage the inputs and outputs of resources. one of the outputs that we have been very concerned here on re:farm is the organic material that a city produce and it’s mostly wasted in big cities. more than wasted, is being mixed with paper, plastics or glass making the “eventualy” recycling process even more painfully. all the organic material produced by our kitchen, restaurants, markets and their super relatives are the raw material for your first step into farming.

you need to get good soil and cheap and this is very easy and simple: our organic waste is food for worms and their waste is food for our vegetables. with this in mind we are gonna setup this new mega composter at Andes and monitor the life of the worms and friends.

the winter is coming so we don’t expect a big grow in the worms population. as everything in nature this will take time. we will follow the live of this object and also see how the materials applied evolve. I’ve design a house for worms with places for them to rest, feed and live. a hexagonal frame?! why not? inspired by nature and a link to the global ecological disaster that is happen right now in the bees superfamily and with their unique position in our live cycle. hard days for our vegetables and belies will come without the bees ;( follow the evolution of this project on this dedicated page

first draw and project concept


this is the first draw of the refarm. the initial idea was to make two systems of growing plants: one, in hydroponic and the other in the classic system with soil. the hydroponic is interesting because you can save water and barcelona is one of these cities that have huge water problems, but soon I left the idea because monitoring this system remotely it’s very expensive. So I stuck with the classical organic/substract system. In the picture you can see what I propose to control: automatic watering system, humidity measure, temperature measure and articial light all controlled by arduino. let’s see where this is going to. deadline: spring/summer 2009