Get answers to Frequently Asked Questions to Groasis

General questions

What is Groasis?
Groasis has been founded by Pieter Hoff, a former lilybreeder, grower and exporter. Through his experience in the flower industry Pieter Hoff learned that worldwide ground water levels decline with high speed. If things don’t change, mankind is out of irrigation water within a few centuries. This thought created the foundation of his company that focuses on the development of producing water from air techniques.

Groasis BVpieter prototype3-1
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Chamber of Commerce Breda 58403396
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What is the Waterboxx?
With the Waterboxx one, two or three trees (also bushes, vegetables, or corn) can be planted in the centre of the box in eroded areas, on rocks or in deserts. In general users will plant two trees. The Waterboxx offers the possibility to plant two trees at a time giving the chance to cut the smallest after the first year and taking care that if one of the two planted has died, you still have one left. This way of planting leads to a close to 100% planting result.

What are the metric conversions?
To convert units (Celcius to Fahrenheit, meter to inch) try a converter.

About the Groasis Waterboxx

When do I use the Groasis Waterboxx?
The Groasis Waterboxx can be used in circumstances where a tree does not get enough water to have the possibility to get started. So the instrument is meant to use in circumstances where there is enough water once the tree has its roots in the soil. On most places on earth, for instance in almost all deserts, there is enough in the soil. The problem is that the seed or the young tree needs a few months or a year help to get deep enough with its roots. You can compare the Groasis Waterboxx with a young seed. In nature it is planted on the soil with the manure of the animal that sticks it to the soil and protects it from eating and from drying out. And by sowing it on the soil the capillary is not destroyed and erosion cannot blow away the soil. Once the seed is germinated and its roots are deep enough, it survives and grows.

The Groasis Waterboxx copies that natural process: it helps the seed or young tree germinate and develop its roots into the soil until it can survive by its own.

How does the Groasis Waterboxx work?
It collects water through capture of rain and produces water through production of condensation, it stimulates capillary and prevents evaporation caused by the sun and prevents competition caused by competitive herbs. It provides its collected water to the tree over a long period of time. Because of this it can play an important role in CO2 capture, anti-erosion and anti-desertification programs, food- and wood production.

  • With the Groasis Waterboxx a tree is planted on top of the soil, so that the capillary is not be destroyed when planting the tree.
  • In the middle of the Groasis Waterboxx there is space to put a seed, a plant or a tree.
  • This plant can develop its roots under the Groasis Waterboxx.
  • The Groasis Waterboxx produces water via artificial condensation.
  • It collects rainwater.
  • It distributes the collected water to the plant on a daily base.
  • It stimulates the rise of the capillary water to the top of the soil under the Groasis Waterboxx.
  • It prevents evaporation of the capillary water.
  • It prevents the development of weeds around the plant.
  • It prevents grazing of the plants by a certain variety of animals.
  • It prevents erosion of the soil around the plant.
  • It prevents heating of the soil around the plant.
  • It stimulates a balanced temperature in the root area.
  • The advantage of planting on the soil is that the Groasis Waterboxx can also be used for planting on rocks.

How many years do I use the Groasis Waterboxx?
In principle the Groasis Waterboxx is used until the moment that the tree can survive on its own. Normally that is after 6 months up to one year. We expect that the Groasis Waterboxx can be used around 10 years so that you can use it for 10 to 20 trees/bushes.

What are the differences between the Groasis Waterboxx and classic irrigation?

  • Classic irrigation is not sustainable. It uses groundwater and the levels of groundwater deepen every year. The Groasis Waterboxx is sustainable.
  • The Groasis Waterboxx is cheap. If you want to start with classic irrigation you need to drill a well, install a pump and a water pipe network and have an electric installation. For the Groasis Waterboxx this is not necessary: just buy a few or a lot and install them.
  • With the Groasis Waterboxx you can plant on rocks. Drill a well in rocks and install a network of water pipes is almost impossible on rocks
  • For classic irrigation in deserts we need to install power installations of electricity. For the Groasis Waterboxx this is not necessary.
  • For Groasis we need very small trees or even seed. That is cheap too.

Is the Groasis Waterboxx only interesting in deserts?
After 4 years of tests we noticed that trees planted with the Waterboxx in moderate climates also show an average growth stimulant of around 15% to 30% extra biomass.

Using the Groasis Waterboxx

Is it possible to plant seeds in the Groasis Waterboxx?
We advise not to plant seeds in the Waterboxx. Always use saplings instead.

How long does the tree need the box?
As soon as you see that the trees starts to grow faster –just notice the growing speed of the young branches- it has reached water and it is able to survive without the box. You just lift it to take it off, replace the old wick with a new one, and re-use the box for the next tree.

What do you do when the stem starts to crowd the hole?
That is the signal that the tree does not need the Groasis Waterboxx anymore. So you lift the Groasis Waterboxx off the tree and use it to plant the next tree.

When should the Groasis Waterboxx be lifted from the tree?
If the growth of the trees goes well, you can sometimes even plant more than one tree per year. You lift the Groasis Waterboxx off the tree as soon as you see that the branches really start to grow fast. This is the sign the tree gives you that he is not growing anymore from the water in the Groasis Waterboxx, but that he found water deep in the soil. In most circumstances, we find that the tree is independent from the Waterboxx after 9 months. You then lift it, replace the wick with a new one, and use the Groasis Waterboxx for the next tree.

Is it advisable to use compost and/or manure?
It is really useful to work with compost if you have it. The trees will grow to 50% faster and will also be healthier. If you have manure, then mix it through your compost. Be careful though: to young manure burns your roots. Manure must be at least one year old before you mix it through your compost.

The instructions say that when you lift the Waterboxx off the tree you have to put compost around it and cover this with rocks. But what if there are no rocks available?
If you take off the Groasis Waterboxx you must cover the soil. The best way to cover it, is with stones but any material will do. If there are no stones, then use straw, weeds, grass or palm leaves. If you don’t have these, you can think of mulch, carton or clothes. If that is also not possible, your last way to cover the soil is with loose soil.

What do I have to do after I’ve taken the box away?
You take off the box, put a cloth made of a natural material (cotton, hemp, coco, wool, etc.) on the same place as where the box was in order to keep the capillary column intact, cover the cloth with 10 cm of sand (4 inches) to prevent it from blowing away and use the box for the next tree. You can also put no cloth but only sand if there is no danger of the sand being blown away.

What will happen to the plant if you remove the Waterboxx after 1 year?
The instructions about the Waterboxx are on this page. As soon as the twigs start to grow rapidly, it is a signal that the tree can survive by itself. You take the Groasis Waterboxx off and you can re-use it for the next tree.

Is the Groasis Waterboxx re-usable?
Yes, you can use the Groasis Waterboxx approximately 10 times in 10 years.

Can I plant everything everywhere with the Groasis Technology?
Planting can be done seamlessly. But it is important to select the right species. After a year without the Waterboxx, you want your tree to keep on surviving. Follow the next steps to make sure your tree will survive.

  1. When you want to plant a tree it is necessary that you choose one that is able to survive under the circumstances. Your variety has to have the ability to resist the temperature and to live with the available amount of precipitation;
  2. If temperatures are above +40 ⁰ C, you can only plant varieties who can resist this. If you have 200 mm of rainfall, you cannot plant varieties who need more than 200 mm to survive;

With this simple rules, you will always have success!

Do you have any minimum humidity requirements for using  in deserts?
No, we even plant in the north of Chile and high, above 4,000 meters in the Andes, where the relative and absolute humidity is extremely low.

Can the Groasis Waterboxx be used on rocky terrain? How can plants grow on rocky terrain?
Yes, the Groasis Technology mimics the principles of nature. On this page you find an explanation about planting on rocks and here you find information about combating desertification.

We also suffer from goats, is there something that can prevent that?
If you look on this page you can see the Growsafe Telescoprotexx plant protector. It protects the plant against grazing animals and it balances the climate.

We have strong winds, is this a problem for the Groasis Waterboxx?
No, winds are not a problem for the Groasis Waterboxx. Look at the strong winds in Dubai in this video. We even offer wind protectors to make sure the Groasis Waterboxx will stay in the right place. You can find them in the Groasis shop.

What is a good and cheap way of fencing an area where you plant trees?
If you want to fence an area, then think of planting 3 rows of bushes, and in between some trees that have dangerous picks, such as the cactus or similar species. Please check our newly developed tree encyclopaedia to find some: http://www.onetrilliontrees.com/en. This is much cheaper than fencing, and it also creates a better micro climate with less wind.

What is the right planting distance?
For ecosystem restoration we recommend a planting density of 10x10 meters with in each Waterboxx a tree and a bush that you also see together in nature. We suggest to start with pioneer trees, because these will create the conditions in which growth and multiplication automatically takes place. And this results in a higher density and a faster recovery process. For fruit trees it depends on the variety, but according to the general rule, you should plant a minimum of 400 trees per hectare, because you do not plant two fruit trees in one Waterboxx.

Which space is required to plant trees?
It is not possible to answer this question. I will give you various details that can help you determine the planting distance between the trees. All this information is based on planting in hot areas:

  1. The annual rainfall defines the species that you can use (as each species has a minimum water requirement). The first thing to do is look for traditional plantations. In general, traditional growers know what is the optimum planting distance is for their trees.
  2. If the rainfall is just enough for the minimum requirement, you can plant less trees per hectare/acre. The size of the tree also defines spacing, if you prune them smaller they evaporate less, so you can plant more trees per hectare/acre. If the soil is sandy, it is dry and poor in minerals. So you plant less trees per hectare/acre compared to when your soil consists of clay and is rich in minerals.
  3. Do temperatures go to extreme heights (up to +45 ⁰C) or do they remain moderate (up to +35 ⁰C). Extreme heights means less trees per hectare/acre. The reason is that for extreme high temperatures trees need water to evaporate, so you give a tree more surface to grow on, this way they have less competition with the other trees, for water.
  4. The same argument is valid for a sunny climate (less trees per hectare/acre) or a cloudy climate (more trees per hectare/acre). Or a southern slope (less trees per hectare/acre) or a northern slope of a mountain or hill (more trees per hectare/acre).

For ecosystem restoration:
I advise to only plant pioneer trees and give Mother Nature time to sow seeds and have other trees colonize the area afterwards. So plant only 200 Groasis Waterboxxes with each one tree and one bush. This way you plant 400 pioneer trees per hectare (160 pioneer trees per acre). That is sufficient. The fact that you only use 200 Groasis Waterboxxes makes this ecosystem restoration model very cheap to do.

How do you plant for ecosystem restoration purposes?
If you plant for ecosystem restoration purposes, we advise using two species in each Groasis Waterboxx. Plant a tree and a bush. When possible, make a combination of species of which you can see in nature that they have a preference for each other. In this way you create a symbiotic effect of faster growth.

Is it true that once a tap root is cut or splits into secondary roots that that tap root stops growing?
During growing in the nursery, the tap root starts to grow twisted round in the pot and many times it will split itself (you do not have to cut the roots at this stage, as it is still growing in a too little pot), caused by being locked up in the pot. This root will keep on growing rounded after planting. The ‘rounded growing’ has been kind of stored in its memory

If I cut a tap root at the point where it starts to grow horizontally, will that tap root be restored and continue to grow vertically or will it just send out vertically growing secondary roots?
Yes, what happens is that you are actually pruning the root. So what happens on top of the plant above the soil  – when you prune it you get re-sprouting of the dormant buds – does also happen below the soil: the pruned root re-sprouts, and these re-sprouts do not have the problem of the “stored memory that tells him to grow rounded”.  Instead of that, it sprouts and grows again as it does originally = vertically downwards. The new re-sprouts do not have the breaking power that the original primary root has, but they are far better than a superficial rounded growing tap root, that stays in the top soil where there’s none or just a little bit of water available for the plant. This is also the reason why so many trees fall down in cities with strong winds. They are just not anchored.

Will the Groasis Waterboxx be damaged while freezing at temperatures below 0 °C (+32 °F) and being full with ice?
No, it will not be damaged. The Groasis Waterboxx is designed in such a way that the expanding ice is able to find room to expand. This is done by designing all the vertical sides in 8°. So when the water expands to ice between +4 °C to -1 °C (+39,2 °F to +30.2 °F) , the ice can just go a bit higher and find room for the expansion. It is also important to understand that it doesn't matter whether it is -1 °C (+30,2 °F) of -30 °C (-22 °F) . Once changed from water into ice – which happens between +4 °C and -1 °C (+39,2 °F to +30.2 °F) - the ice doesn't exapand any further.

How can I implement an anti-desertification tree planting project with the Groasis Technology?
Groasis Waterboxx Project Implementation Information

What trees are best suited for the production of fuel wood?
Please check the document that you find in the link to find some suggestions for trees to use. Especially the gmelina is a fantastic tree to produce fuel wood. 

The water in the Groasis Waterboxx

Does the water in the box become dirty after a while?
The water in the box remains clear and has no problems with bacteria, algae or what so ever.
How long does the tree need the box?

What type of water can be used for plant growth? Can potable water, dirty water or saline water be used?
Yes, all types of water can be used. But with saline water the tree must be able to deal with this kind of water.  In this report, about planting  in La Chocolatera in Ecuador, which is one of the hardest places on earth to plant a tree, you find more information about planting with saline water.

If you use the Groasis Waterboxx in the desert, do you need water or is the water extraction from the air sufficient?
You have to use one time 60 litres of water while planting. Afterwards you do not have to refill it anymore. Watch this video for more explanation:

On what basis is 60 litres of water calculated? Is it calculated on the basis of growing particular type of tree?
There is actually no optimum general quantity. Each species needs, each soils characteristics and each valley’s climate are different. However, it is impossible to communicate a manual for each soil type, each species and each climate. This advise works worldwide on each species, each soil and in each climate. Suppose you have a Tara tree (Ceasalpinia Spinosa), clay soil (that has a better water fixing capacity than sand) and moderate circumstances (temperatures do not rise above +35⁰ C). Then you can use less water. Suppose you have a Tara tree (Ceasalpinia Spinosa), sandy soil (that has a little water fixing capacity) and hot circumstances (temperatures above +45⁰ C). Then you need more water. Our advise of 60liters is therefore a safe average advise. So in general people start with the advise and investigate their own local optimum.

What if there are logistical problem with the 60 litres of water that the Groasis Waterboxx needs?
I know that solve logistical issues in desert areas is not easy, but the quantity compared to irrigation is really small:

  1. Groasis Technology: once in a life time 60 liters
  2. Drip irrigation: eternally each day 15 liters

On this page you can find an Excel document with a comparison of costs between the Groasis Technology and the drip irrigation technology.

How many times do I have to refill the box?
You only fill it one time during planting. The box will then catch enough rain or condensation by itself to supply the plant one whole year.
How many rain does the box need to fill itself?

How many rain does the box need to fill itself?
75 mm (3 inches) of rain is sufficient to fill the box completely.
Will the Groasis Waterboxx be damaged while freezing at temperatures below 0 °C (+32 °F) and being full with ice?

How will trees survive if the ground water is too deep in the desert? Can roots go that deep into the soil in one year?
Trees do not survive on groundwater, but on capillary hang water. The deepest roots ever found are 84 meters. Many times groundwater in deserts is deeper than 84 meters. The capillary hang water is the water that penetrates in the soil during the annual rain. For example:

Suppose you have 300 mm of rain. Of this 300 mm, 100 mm  does not penetrate, because the soil is very hard or because there is a steep slope. Only 200 mm of the precipitation enters. Then you can plant trees:

  1. That resist the climate (cold, hot, strong winds);
  2. That can survive with 200 mm.

So it is important to understand that:  

  1. The annual rainfall says nothing about the quantity that enters the soil
  2. Trees do not survive from groundwater but from capillary hang water caused by the penetrated quantity of rainfall.

When the cover of the Waterboxx is covered with sand and the openings are clogged, does the condensation process still work?
When the top of the Waterboxx is covered with sand, the condensation does not work. The collection of rain is no problem, it will still enter the box. If there is no condensation we have less water available. However, the functionality of condensation is not influencing the box’s planting result. In the whole Middle East, and many other desert areas, it is so warm at night, that no condensation occurs. We however still have excellent planting results.

Can I only plant once a year when there is one rainy season?
You have to distinguish two ways of planting after the first stage:
The first stage is the planting of the saplings in pots. This can be done with either seeds, or via cuttings. After that you can work in two ways:

  1. In two phases. First in a small plug (width x height = app. 6x10cm) and then transplant to a big one (width x height = app. 12x15cm).
  2. In one phase: immediately in a big pot or plastic bag.

I suggest to work in two phases. So first the small plug, then the big pot or plastic bag. The reason is that the germination of the seeds, or the rooting of the cuttings is a risky process, and if you have only 50% success ratio, you lose little space and little expensive soil.
Always check what the local experiences are, but in general we can say that in the tropics, where day length is approximately equal, you can sow your seed or make cuttings almost all year round.

Outside the tropics, either in the northern or southern hemisphere, you can plant or sow with the season, once a year. For the Groasis technology we need saplings that are at least one year old. So after one year of being in the big plastic bag in the nursery, we bring the saplings to the field.

With the Groasis technology you can plant any day of the year in the tropics. Outside the tropics you can also plant any day, if the frost is not colder than -5 ⁰C (+23 ⁰F). When you expect a colder frost, we advise to stop planting after October 1 in the northern hemisphere, and start again after the winter.

Costs of the Groasis Waterboxx

Some people say that the cost to plant a tree with the Groasis Waterboxx is 20 USD?
If you buy a car that costs 20,000 dollar, you do not say that the first kilometre costs you 20,000 USD. If you drive the car for four years and each year you drive 50,000 kilometres, you drive 200,000 kilometres. This means that the investment is 20,000 USD and the costs of the car are 10 cents per kilometre. We cannot mix the concepts of investment and costs. So the investments of the box is 20 dollars and the annual costs are 2 dollars. So the cost per tree are 2 dollars.

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