| Hydroponic
cultivation is considered by many to be the superior method of agriculture
both on a commercial level and for personal crop production. Plants
are fed their exact nutritional requirements, provided with controlled
environmental surroundings and supplied with their precise lighting
needs. Nature could not offer better growing conditions!
The
incredible part about hydroponics is.it's easy! Or at least it
should be. Over the past decade the insurgence of pseudo-scientific
information in the hydroponic industry has become dazzling. There
are additives, boosters and supplements for your nutrition regime.
New liquid tonics or powdered concoctions pop up daily with a promise
to increase nutrient uptake, keep roots strong and healthy, accelerate
growth and increase flower size and fruit flavour. There are detoxifiers
and leaching solutions and an abundance of other additives that
your plants can't do without. or so the savvy marketing people would
have you believe!
The
web offers a wealth of ideas on hydroponic growing, each site offering
information skewed to the particular products sold by the owner
of that domain. Wading through the labyrinth of information can
be mind boggling.
As
with anything the consumer must also be savvy and educate themselves
about the different products available. Understanding what a plant
actually needs to sustain life is crucial to help sort through the
rhetoric.
To
understand what growth influencing factors (GIF's) are to a plant
is to understand basic plant physiology. Any one of these GIF's
plays a big part in continuance of a plant's life: Light, potential
hydrogen (pH), carbon dioxide (CO2), oxygen (O2),
temperature, humidity and nutrition.
Light
requirements can be met with natural sunshine or with an artificial
light source. (CO2), (O2), temperature and
humidity can all be controlled by the grower. Plants will survive
in the same comfort environment as humans so it is not difficult
to supply an adequate amount of these GIF's. However, supplementation
or tighter controls of these GIF's may optimize growing conditions.
pH
is the level of acid or alkalinity of your nutrient, pH 7 being
neutral. The pH level of your nutrition solution determines the
plant's ability to use the food efficiently. pH is easily maintained
at the proper level by a simple litmus paper test and then adjusting
as necessary.
In
hydroponics plants absorb nutrients through their tiny root hairs.
The roots will only take up as much nutrition as they require.
It is impossible to overfeed in a hydroponic system, however, mixing
a solution too high in nutrient levels will result in root dehydration.
All
plants require a balance of nitrogen, phosphorous and potassium
(N-P-K) and trace elements to grow properly. The other GIF's influence
a plants' ability of utilize these nutrients adequately.
There
are 20 macro and micro-nutrients required for plant growth:
Macronutrients are required in large amounts |
Carbon |
C |
Component of all organic compounds |
Oxygen |
O |
Supplied by air & water |
Hydrogen |
H |
Combines with oxygen to form water |
Nitrogen |
N |
Part of chlorophyll, amino acids, proteins |
Phosphorus |
P |
Used in photosynthesis and almost all aspects of growth |
Potassium |
K |
Activates enzymes, used in formation of sugar and starch |
Calcium |
Ca |
Used in cell growth and division, part of cell wall |
Magnesium |
Mg |
Part of chlorophyll, activates enzymes |
Sulfur |
S |
Part of amino acids and proteins |
Micronutrients are required in trace amounts |
Boron |
B |
Affects reproduction |
Chlorine |
Cl |
Aids in root growth |
Copper |
Cu |
Used in chlorophyll, activates enzymes |
Iron |
Fe |
Used in Photosynthesis |
Manganese |
Mn |
Part of chlorophyll, activates enzymes |
Sodium |
Na |
Used for water movement |
Zinc |
Zn |
Part of enzymes, used in auxins |
Molybdenum |
Mo |
Used in nitrogen fixation |
Nickel |
Ni |
Liberates Nitrogen |
Cobalt |
|
Fixates Nitrogen |
Silicon |
|
Makes tougher cell walls:
enhances heat and drought tolerance |
Small
amounts of these nutrients can be assimilated through healthy soil,
however they are quickly depleted rendering the soil void of all
life sustaing properties.
In
hydroponic cultivation essential nutrients are provided in ideal
proportions. The inert growing medium does not contain any nutrients.
Through extensive research conducted in the 1920's (and much trial
and error) scientists were able to determine a very specific blend
of mineral salts that when mixed with water would completely nourish
plants. Immersing plant's roots directly in this solution proved
to be very fruitful and lauched the way for modern hydroponic practices.
The refinement of this technique of cultivation has been on-going
ever since.
The
word hydroponics was derived from the Greek word 'Hydro' meaning
water and 'Ponos' meaning working, literal translation, water-working.
Today's definition of hydroponics is 'soilles cultivation' which
means simply, growing without soil.
The
simplicity of hydroponics has been vastly understated. It is easy
to grow almost anything hydroponically. Our North American society
insists on complicating things. Sure there is a benefit to using
some of the additives and supplements available to enhance crop
production. But, if you are just starting out it may be wise to
keep things as basic as possible. Hydroponic windowsill gardens
are available and ideal for planting low light plants. Fresh herbs
can be grown in a kitchen window ready for use in any recipe. A
small 4' x 4' garden can be easily maintained and will yield a profusion
of crops.
Nutrition
is an intregal part of good crop health and a successful yield.
Start off very basic using a high quality concentrate nutrient.
Any reputable hydroponic shop will be able to advise you on which
product to choose. Most nutrient formulas are 2 or 3 part. This
is because these fertilizers contain mineral salts which, when mixed
together in a concentrated form will bind together causing them
to fall out of suspension. Follow the manufactures instructions
carefully and only mix each part into the water.
Hydroponic
formulations are structured for the different stages of growth.
A plant's nutritional requirements shift from their vegetative stage
to their flowering stage therefore, there is a grow formula and
a bloom formula.
Plants
need higher levels of nitrogen during their vegetative cycle. Nitrogen
is the key mineral in the healthy development of leaves and stems.
It is also the most common deficieny in plant growth resulting in
stunted growth and yellowing leaves. During the flowering cycle
the ratio of nitrogen to phosphorous and potassium is decreased.
Following
a good nutrient regime should be enough to produce a high quality,
vitamin rich food source. Keeping it simple means less troubleshooting
should a problem occur. Creating a toxic soup of addivtives and
supplements makes it very difficult to find the culprit if something
does go wrong.
The
more advanced growers may wish to fine tune plant nutrition by supplementing
the twenty mineral elements required for plant growth (and contained
in good quality hydroponic nutrients). Natural hormones, vitamins
and some rare trace elements will stimulate normal biological functions
in plants. There are other products designed to help facilitate
faster nutrient uptake and accelerate stem and leaf growth. Discuss
the various options with your hydroponic retailer and, if it sounds
too good to be true.well, you know the rest!
Great
care should be taken when using these growth boosters. Only introduce
one new product per crop rotation. Try not to get carried away
by the promise of bumper crops that are ready to harvest in half
the regular time.
Bloom
fortifiers are useful to supplement flowering and increase essential
oils in plants. Look for a fortifier with a NPK ratio of 0-50-30.
This indicates that there is no nitrogen and very high levels of
phosphorous and potassium. Both of these essential minerals increase
the development of super blooms.
Organic
gardening practices have become very popular over the last decade.
The hydroponic industry has made great strides in developing organic
formulas that will work well in a hydroponic system. An organically
based nutrient should be a soluble, stand-alone product that has
no sediment on the bottom of its container. Be wary of organic
formulas that require shaking before use. This could be an indication
that the product contains sediment that will clog lines and pumps
used in a hydroponic garden. Never attempt to use an organic fertilizer
that is designed for soil applications in hydroponics as it may
result in plants burning and lines getting blocked.
Kelp
is very safe and an excellent source of organic trace minerals.
Used regularly as a foliar spray, kelp is great way to help avoid
nutrient deficiencies. Kelp spray will also act as a pest deterrent.
Regular
reservoir changes every 7 to 10 days will ensure that fresh nutrients
are always available to meet the demands required for healthy growth.
An electro conductivity (EC) meter will help regulate the optimum
amount of nutrient required. Always check pH after the nutrient
solution is mixed.
Leaching
or rinsing is necessary to wash out any excess salts that remain
in the growing medium. Leach about 1 week prior to harvest. Run
regular tap water or reverse osmosis water through the system following
the established feeding times.
It
is always wise to keep a journal of your gardening adventures.
This will allow you to repeat successful harvests and avoid duplicating
mistakes. Record information on a daily basis such as: Species,
germination date, nutrient brand and feeding times, pH, EC, leaching
date and harvest date. Don't forget to record the time and dose
of any additives used.
Keep
it simple and enjoy the fruits of your labour. A hydroponic garden
can be a fascinating and rewarding hobby year round.
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