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Metrop plant grow info, science.

PH factor.

The PH factor of the medium is very important, but also the most done wrong factor.
A plant transports the elements in water. Therefore it is important that the elements can be connected with the water for an optimal intake by the plant.
This depends of the PH value of the element.
The best PH value for each medium is between 5.4 and 6.2

Ph value schedule
The availability of food elements depends on the PH.
The width of the band shows the intake.

Would for instance the PH be too high, then the Phosphorus, Manganese and Borium intake would be a lot less, with shortcomings of these elements and the burning of the leaf (each time water is given, it piles up) as a result.

Would the PH be too low, there would not be an optimal intake of all elements, which results in shortcomings again and the burning of the leaf.

The PH has to be measured in the medium and not in the barrel or drainage water.

Measuring PH:
The best way to measure this in a hydro or NFT system is to withdraw some water with a syringe from the medium and then to measure it.

With soil or coco you measure it with a special soil meter, if you do not own one, then 30 minutes after watering take a wet sample, from the pot. Put it in your hand and push in the PH measurer.
By pushing in the soil, fluid releases where the measurer can take an exchange from and you will have the exact PH value of the soil or coco.

The PH depends on the buffer quality of the medium and of the water (amount of bicarbonate).
When the buffer is full or just gone then the PH will change to very low or high values.
A lot of problems with a too low PH can easily be solved by for example placing a new buffer.
AZ grass calcium is a good solution for this, but be careful, too much will increase your PH again.
Copyright Metrop Hydroponics 2004

Light/ dark/ hormones:

The proportion between light and dark (day and night) we call the photo period.
Blooming starts when the days get shorter, growing and blooming of the plant is influenced by the hormone Fytochrome.
The plant makes this hormone day and night but breaks off during the day by light.
The hormone will gain the upper hand when the plant is in the dark for 12 hours in a 24 hour period and will start the blooming of the plant.
A small amount of light in this dark period can interrupt the blooming process or even completely stop it.
That is why it is very important never to enter a dark room, not even with a flash light.

If the light is set for 18 hours, the hormone will never gain the upper hand and the plant will remain in a vegetative stage and will only keep on growing.

Light is also important for producing energy.

6H2O + 6C2O—LIGHT -> C6H12O6 + 6O2

Easier said:
Water + carbon—light=> energy

The more light, the more energy a plant can make provided that there is enough water and CO2.
A trick some growers use is , in the last 2 weeks of the blooming period to up the light from 12 to 14 hours.
The plant has enough hormones in it, to keep on blooming but gets 2 hours of light more a day to make more energy (and 2 hours less dark to use the energy).
Copyright Metrop Hydroponics 2004


EC stands for Electric Conductivy (ms/liter) and with that we measure the amount of useful and useless salts in water.
The EC measurer simply measures the amount of electric resistance, and that also explains why a medium like soil needs to be “wet” to be measured.

An EC measurer measures a total of all nutrition salts.
An EC of 0.1/100 liters from one brand, might not have the same nutrition value as one of an EC of 0.1/100 liters from a different brand.

In most cheaper plant foods, there are a lot of elements like chloride, cadmium and other filthiness. These salts will all be measured by the EC.

Growers who grow their plants on weight want to have a large intake of salts (nutrients) for a heavier end result.
These salts have to be available and be available for absorption, in a balanced way that it stimulates the absorption.

The best way to measure this in a hydro or NFT system is to withdraw some water with a syringe from the medium and then to measure it.
For soil and coco, mix the mediums lightly with distilled water in a cup, and measure it after a short period. Regular water will also work, but will be less secure.
Copyright Metrop Hydroponics 2004


Temperature is an important determining factor.
If the temperature is not right, the plant will grow less or not at all.

Science has taught us that the best temperature around the leaf is 24-26 degrees Celcius for all vegetation, for a maximum of growing and blooming day and night.

During the day the plant makes energy to grow (assimilation) and at night the plant uses energy to grow (breathing).

The art of growing is to make sure that during the day the plant makes as much energy as possible and that at night uses the least amount of energy as possible.

We can stimulate this during the day by adding more CO2 and more light, and to stimulate the evaporation under the leaf (with mature plants) by air circulation.
Copyright Metrop Hydroponics 2004

plant energie / temperature growth schedule
Energy/ temperature graph:
Assimilation –breathing – growth


Stimulants, also called boosters, sometimes all work the same way, by amino acids.
Some of them might have some hormones mixed within, but the basic is always amino acids.

Amino acids you can gain from fermentation, hydrolysis or by the complicated process of biosynthesis.

An amount of amino acids together form a helix.
A helix penetrates a cell wall, but needs to be smaller then 1500 Dalton (length measurement) before the cell wall will let it thru.

The helix will end up in the nucleas, where the DNA is.
DNA structures are like small switches, where every switch has its own function.
Functions like the width, length, color, etc of the leaf till the whole form of the plant, under and above the ground.
A plant always has stress, especially when it is a clone of the mother plant, that time and time again will be cut and needs to be repaired.
The stress will show up on the leaves, for instance with plants with finger forming, less fingers will appear.

Certain amino acids together who will form a helix, are like a key, that will only fit on 1 DNA switch, and will attach to this one.
Actuelly they take the “stress” away and will take care of optimal growing and blooming of the vegetation.

growth / bloom stimulator

> Fermentation/hydrolysis:<
The disadvantage of fermentation and hydrolysis is that it is limited to the amount of different helixes and with that, the amount of functions. What is in it, is in it and can not be changed only be diluted.
Diluting is done so massive sometimes that these products have no functions left.

Also are these so called organic products sometimes polluted with impurities like heavy metals which are toxic and biologically dangerous for the plants and for humans.

An other disadvantage is that the amino helixes are longer then 10.000 DA, by which the absorption of these helixes takes longer, because they have to be made smaller by the plant ,with the help of enzymes.

> Biosynthesis:<
The advantage of biosynthesis is that several different helixes and so more functions, can be changed and multiplied. A product made by biosynthesis stimulates for example not only the different root functions but also the making of the hormones and the forming of the leaves and stem.

These amino helixes are also free of impurities, and diseases which is better for the health of the plant and of humans.

An other advantage is that amino helixes from biosynthesis are only 700 DA long and therefore absorption can happen immediately by the plant cells, and stimulate the growth and blooming process right away.

A disadvantage of biosynthesis is that it is a technically complicated process, and so these products are hard to get.
Copyright Metrop Hydroponics 2004

growth / bloom stimulator
AminoRoot plant roots stimulator / plant grow stimulator
AminoBloom plant stimulator / flower stimulator.

Calcium in plants:

Next to nitrogen, phosphorus and potassium is calcium the 4th most important fertilizer for a plant.
Adding calcium to the medium, brings more food to the plants by pushing away the ions.
Furthermore the calcium advances the analysis of organic substances, thru which more nutrient elements will be available.
The proceeds of the harvest will rise after adding the calcium, but the medium only seems to be more fertile.
In reality the medium pauperises, because the plant will have a bigger intake of food.
By simply fertilizing more fertilizers, we solve this problem, which results in higher proceeds of the harvest.

Calcium is essential in a plant. It binds acids which would poison the plant.
For example, oxale acid and calcium sit together with protein in a certain connection in the cell wall.
If the plants do not contain enough calcium they will form long weak stems.
The leaves will also be weak and the roots do not form optimal.

For the build up of calcium and protein in the plant cells borium is needed.
It will act like a brick layer to build these elements within the cell walls.
Only the PH of the medium needs to be lower then 6.0 in order the absorp the borium.

Calcium in plantsplant grow information

Because calcium protein with the help of borium (it becomes vitamine B12) strengthens the plant cells, it will result in a stronger plant with less chance of rotting and mould forming and a more profitable end result.
Copyright Metrop Hydroponics 2004


Mistakes can be made with fertilizing, the most common mistake is disturbing the balance, by one sided adding of too much of certain ions (salts).
The colloids (buffer) partially repair this mistake, by fastening the ions.
They will disappear out of the fluid from the soil, which prevents the surplus of salt.
This surplus would have an adverse influence on the cell fluid from the root hairs.
The water would be withdrawn from the cell fluid by the high concentration of ions outside the cell.
This would go on till there is a balance of salts inside and outside the cell.
This water withdrawal is also called ”burning of the leaves or plant”.

Cheaper fertilizers contain a lot of salts, who are only partly plant food.
These salts, sometimes called “ballast material” can make it happen that the plant will burn sooner because they pile up in the medium.
The medium will, as a result, not be able to be used again for a next time and needs to be replaced.
Cheaper fertilizers will cost more, next to a smaller harvest, more labor and money to replace the medium.
Copyright Metrop Hydroponics 2004


Humidity might be the most under estimated growing factor.
The relatively humidity RL, we use as a unit to measure or change this.
Dry air will accelerate the evaporation of fluids from the leaf and moist air will delay this.
A plant always has to be able to evaporate some water, in order to retrieve new water from the medium which contains new nutrients.

A plant is almost like a pump working on solar energy.
Only when the RL is too low, the plant will evaporate more then it can absorb and will end up with a grow disorder or even dry out.
If the humidity is extreme high the plant will eventually not grow.

So a balance is very important.
Small cuttings do not have a lot of roots so therefore can not absorb a lot of water.
To let a cutting grow the hardest the first 3 weeks, you will need an RL of 80 %.
After that, thru the 6th week, the optimal RL is 60%.
In the 7th week and later we bring back the RL again , but not under 40%.
Evaporation under 40% goes very fast and therefore hard for the plant to absorb new fluid.
As a reaction the plant will close it’s skin mouths, which will stop the growth and the blooming.
This stop will reduce your harvest.

Important is also the temperature of the humidity.
There are systems who easily blow cold water in the air.
This cold moist will delay the growth.
Better is to use lukewarm water.
Hobby growers who do not have the use of a humidifier, should fog their leaves the first 6 weeks.
Copyright Metrop Hydroponics 2004

Carbonic gas CO2:

In the air we find carbon as CO2.
It is brought in the air thru breathing of plants and animals and thru burning and perishing of organic materials.
Botany teaches us that CO2 is made out of water and sugar.
From here starch, fat and cell material is come into existence.
Protein also contains carbon.
That is why is it is understandable that the dry material of a plant exists for 50% out of carbon.
For the build up of a plant carbon is an important element.
The air holds 0.03% carbonic acid, this small amount is however enough.

6H2O + 6CO2—light –>C6H12O6 + 6O2

In other words:
Water + carbon—light => energy
The more CO2, the more energy a plant makes, provided there is enough water and light.
Growers that create a high oppression (by large suction installations and small openings) will by thin air(small amount of CO2) always receive smaller plants if they improve the air pressure.
Copyright Metrop Hydroponics 2004

Rhizo bacteria and Trichoderma moulds:

With the help of soil life, plants can create a natural resistance against diseases and attacks.
Bacteria we can distinguish in bad bacteria and good bacteria, the so called Rhizo bacteria.

Rhizo bacteria we can distinguish again in 3 groups:
1. The nitrogen binding bacteria
2. The phosphate free making bacteria
3. The hormone producing bacteria

Roots expel sugars and bacteria come to the sugars.
Rhizo bacteria need to get the upper hand over the bad bacteria to prevent diseases and make food available for the plant.
The easiest way to do this is simply add these bacteria.
Another advantage Rhizo bacteria have, is that at the root points, they can change a wrong PH into a right PH.

A root can fill up a maximum of 10 % of the pot, more is simply not possible.
We can up the capacity of the roots with root moulds, the so called : mycorrhiza moulds.
Because the mould threads grow meters from the roots and are microscopically thin, they come to places the roots can never reach.
The root system of these plants becomes hundreds of times larger then of plants without the mould threads, all in exchange for a bit of sugar.
The threads excrete some of the sugar they do not use around the threads, which attracts the already available Rhizo bacteria.
Because the Rhizo bacteria are present around the mould threads, what stimulates the nutrient intake, the PH of the soil will be just right.

A liquid bacteria preparation however can not be kept long ,because bacteria need sugars to survive.
Without sugars bacteria only live for 3 days.
A liquid preparation with sugars would expand in a short time (bacteria multiply) and the bottle could explode.
If the sugars are gone the bacteria die.
That is why you seldom see liquid bacteria or enzymes in the agriculture or horticulture (or it is fake).
Copyright Metrop Hydroponics 2001

Metrop Hydroponics links:

Soil/Coco/Hydro grow fertilizer
Soil/Coco/Hydro flower fertilizer
Soil/Coco/Hydro motherplant fertilizer
Soil/Coco/Hydro Amino roots stimulator
Soil/Coco/Hydro Amino grow stimulator
Soil/Coco/Hydro Amino flower stimulator
Soil/Coco/Hydro Hydroponics Calcium Magnesium fertilizer
Metrop Hydroponics H2O2 fertilizer
Soil/Coco/Hydro organic silicon fertilizers
Soil/Coco/Hydro organic poison fertilizers
Organic sulfur fertilizer
Soil growschedule
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Hydroponics growschedule
Fullwater growschedule
Indoor Foliar growschedule
BIG shop Belfast
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