Recycling yogurt pots to produce seedlings with less water and fertilizer (Willem Van Cotthem)

Mini-greenhouses, first step to combat desertification

This is the first part of a description of “mini-greenhouses”, made of simple and cheap materials like yogurt pots, soda or juice bottles, mushroom trays, plastic bags etc. This kind of inexpensive equipment to produce seedlings of vegetables and trees, e.g. fruit trees, is available all over the world and almost free for all the poor, both in rural and urban areas.

Left: Lower part of a pot used as cup, standing on the lid - Right: yogurt pot to be used as "roof" over the cup (Photo WVC)

Seedlings can be grown in mini-greenhouses with a remarkable minimum of irrigation water (saving both water and fertilizer!); they can easily be transplanted in family (kitchen) gardens or school gardens and their survival rate is dramatically higher than that of seedlings or saplings grown with classical gardening practices.

Sorgo seedlings growing in the cup

The many advantages of this method make it an efficient first step to combat desertification and to get around the problems of drought and soil poverty:

  • To produce a maximum of seedlings with a minimum of water and fertilizer,
  • To grow seedlings in disposable pots, bottles or bags,
  • To grow seedlings close to the house instead of in the field,
  • To avoid the manifold problems of the garden soil,
  • To make use of significant educational aspects.

I intend to publish a number of variants on mini-greenhouse construction:

Part 1: Yogurt or other plastic pots.
Part 2: Plastic bottles
Part 3: Plastic trays
Part 4: Plastic bags

On all continents these materials are generally littered, dramatically enhancing pollution.  Streets and squares, road sides, fields, thorny trees, even the deserts are literally besmeared with all kinds of plastic objects in the most diverse colours.  That dirty plastic is not only degrading the environment, it is also the source of many diseases, e.g. by condensing sewage water underneath the plastic in the gutter.  Therefore, it is recommendable to teach youth how to “recycle” plastic bottles, pots, cups, trays, bags and the like by “recycling” them for seedling production in mini-greenhouses (see below).

Part 1 : Yogurt or other plastic pots

On March 19, 2008, I already posted on this desertification blog  an article on the use of yog(h)urt pots as mini-greenhouses described as follows:

“A major part of my life has been dedicated to the combat of desertification and alleviation of poverty, in particular that of rural people in the drylands. One of my main objectives is to find cost-effective ways of helping these people to get better standards of life and to offer them opportunities to apply the best practices in that combat of desertification. Success stories have been registered all over the world. Unfortunately, they are neither well known, nor applied at the largest scale.

Although some very efficient and cost-effective technologies and methods have been repeatedly described and recommended, their application rate is still dramatically poor. One wonders why it is seemingly easier for international and national organizations to spend billions at enormous programs and projects than to provide reasonable financial means for large-scale application of these inexpensive, but highly efficient best practices.

It may sound a bit discouraging, but it is not. Indeed, the day will come that decision-makers will be aware of the necessity to turn to simple, efficient methods, instead of spending too much at non-productive and unsustainable initiatives. Not the profits for shareholders is important, but the welfare of the poorest.

That is why my personal interest is focused on simplicity and cost-effectiveness, e.g. recycling waste or saving valuable seeds from the garbage bin or compost heap (see our project “Seeds for Food” at and  One should never forget that viable seeds contain the embryo of new plant life!

Continuously looking for new opportunities for container gardening, a wonderful method for producing food in the drylands, I did a lot of experiments with all kinds of transparent yogurt pots. I thereby found an easy way to transform these pots into mini-greenhouses for a windowsill or a table close to the window.

Below you will find some pictures explaining the functioning of my new (?) mini-greenhouses, in which small quantities of seedlings can be grown before being transplanted. Maybe someone did the same before, but up to now I didn’t find traces of this method. Should you have more information, don’t hesitate to send it to me.
2008-03 (178) – Mini-greenhouse made of 2 yogurt pots. Left: Lower part of one pot (cut off with small scissors) used as a cup and put on the lid of that pot. Right: the second pot without its lid.
Mini-greenhouse before filling the cup inside with potting soil.  Notice the 4 aeration holes at the top.
Left: cup with Sorghum-seedlings in potting soil.
Right: yogurt pot used as cover.
2008-03 (185) – The yogurt pot, covering the cup with Sorghum seedlings completely by pushing it in the lid underneath, is perforated (4 little holes) to allow minimal evaporation and penetration of oxygen inside the pot. The covering pot can be lifted from time to time to “harden” the seedlings before they will be transplanted.
2008-03 (186) – Set of 3 mini-greenhouses with cherimoyas (Annona cherimola), lychees (Litchi chinensis) and sorgho (Sorghum bicolor).


A large number of seedlings can be produced this way. It’s a very interesting method to produce tree seedlings with a minimum of water. These seedlings can later on go to the field or garden; they can also be transplanted into a plastic bottle to allow further growth before planting them in the field.

Advantages of this method:

  • Possibility to grow seedlings indoors (even before Spring in temperate regions, like in Belgium).
  • Possibility to grow seedlings with a minimal quantity of water (avoiding drought outdoors) inside the house in the drylands (not in the garden outside).
  • Easy way to check germination daily.
  • Easy way to regulate moisture level in the “mini-greenhouse” (lifting the transparent yogurt pot, covering the seed(lings), to aerate whenever needed).
  • Opportunity to choose the right moment (dimension of seedlings) for transplantation.
  • Opportunity to reuse the same mini-greenhouse multiple times (easy to clean after transplantation).


This is a method that can tremendously help rural people in the drylands. It suffices to offer them free heaps of “yogurt pots” (which should not be littered anymore, but washed and cleaned!) to have them growing seedlings of certain crops in an optimal way, without having to irrigate their garden daily with a huge quantity of water (isn’t saving water in the drylands a MUST?).

I wonder if one could not set up local or regional collecting points for these yogurt pots and offer them to NGOs for their development projects in the drylands. Impossible? Give us a good reason!

Anyway, it would be much easier than constructing a dam or a borehole to get more water.  For sure, mini-greenhouses are a giant step forward in the combat of desertification, because saving a lot of water is a primordial task in all the drylands.

Let us go for it!  And if you don’t believe in it, just give it a try.  You’ll see!

Author: Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.

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