17 essential tips to help you with hydroponic gardening
1. What is hydroponic gardening or Hydroponics
Hydroponic gardening or 'Hydroponics' is emerging as a trend for conscious omeowners, looking at opportunities to grow organic produce
for them and their families. The plants can be fully traced through the purchase and growth cycle, to ensure no harmful chemicals or pesticides
are used, and with the added benefit of having a relatively quick growth cycle compared with soil.
Hydroponics is basically the process of growing plants in a solution of nutrients and water, without the need for soil. It is a derivative
of hydroculture with the difference being that instead of using a solution of nutrients in water as the growing medium an inorganic solid
growing medium is used, the (inert) inorganic solid growing medium is usually a mineral aggregate like rock, or ‘expanded clay aggregates’,
expanded clay aggregate (ECA) is made by heating clay to 1,200 degrees Centigrade or 2,190 degrees Fahrenheit in a rotary kiln.
The hot gases expand the clay forming thousands of small bubbles, in a honeycomb structure. The honeycomb structure gives it properties
including strength and durability, the finished form of the clay, is circular this is a result of the circular movement of the kiln.
2. Benefits of growing using a hydroponic garden
2.1 Growth speed
According to experts, plants growth speed is approximately 20% faster in a well maintained hydroponic system, this means such system represent a
significant time saving benefit, in the cycle time from planting to yield, compared to soil.
2.2 Increased yields compared to soil
Yields from the growth are also larger, with scientist recording between 20%-25% more yield than soil, such a significant increase in return on produce, when compared to soil.
means more yield can sustain longer food reserves as well give favourable returns on investment.
2.3 Space saving
Space saving is another benefit, given the medium the plants are immersed in. Also, the roots don’t need to spread out as much to get the nutrients they need, the oxygenated nutrient
rich water, which makes up an essential part of hydroponics, allows the plants to be packed together more closely creating a smaller footprint. This is a huge space saving benefit meaning you can put more
indoor plants together and grow them in a smaller space. For urban homeowners who are looking to grow a variety of plants in a small space, this represent a viable solution.
2.4 Reduced water requirement
Water saving can be made as reservoirs are used, and they are used in a contained manner (preventing evaporation). The containers are also sealed around the base, preventing water leakage and loss,
this means the plants can absorb what they need, whilst the reservoir holds the water they don’t absorb, until it is needed.
With soil, plants, must be watered daily to compensate for water that is wasted, and consumed. It is noted that
the same amount of water soil uses in a day, can be used to feed a hydroponic based plant for days or
even weeks at a time. This can be up to about a 90% saving on water usage, cost and application when comparing hydroponics
2.5 What! No weeds
Gardening with soil comes with managing weeds, this is frustrating, time consuming and costly. With hydroponics there are no weeds to manage, which
means less frustration and more time managing the crop.
2.6 Guess what no pests and diseases
The absence of soil in hydroponics means you can also remove soil based pest and diseases, and the damage they cause to your plants.
3. Ebb and flow
If we focus on the beginner hydroponic gardener, someone who is looking to get started then the three best systems are wick, water culture, ebb and flow. Each system can be self constructed based
on individual components that you can purchase, or as kits, which can be purchased online at specialist stores such as https://www.growell.co.uk
This is the most recognised system of hydroponics and also the most complex, it involves, a cycle of flooding the nutrient rich water medium, and then draining it into a reservoir tray.
The system requires a fill tray at the top, which contains the plants submersed in the rich water solution, a secondary reservoir container (minimum 1 foot deep) is placed beneath the tray, this has a submersible pump with a timer,
the pump hose is inserted into a hole in the base of the tray, which uses the timer to periodically pump the water into the fill tray, a secondary pipe is used as a drain to release the surplus water from the fill tray back into the reservoir,
and this represents the cycle, it is possible to regulate the watering schedule depending on the various environmental factors, humidity, temperature, etc. The volume and number of potting plants, individually or in a group is also an option with this method as well as
filling the tray with water and planting seedlings directly into the an ECA base.
4. Water culture systems
Using a reservoir, container at least 1 foot deep fish tank or water container. A Styrofoam raft is placed on top of the water medium, ECA clay balls and seedlings are placed into the raft pots. Holes are then cut into the Styrofoam,
to accommodate the different plants bested in net pots with perforated bottoms, this allow the ECA and seedlings to be submerges and the roots to grow into the nutrient rich water medium. The Styrofoam raft acts as a float for the pots to remain emerged
and the plants to grow above the waterline. An aerator or air stone should be submerged just above the bottom of the reservoir, this ensure the nutrients do not become stagnated, the stone is connected to an outlet air pump via air tubing and sits directly
outside the reservoir, it is also essential to purchase the proper nutrients and equipment for monitoring the pH level of the water.
5. Wick systems
The wick system is the most simplest and basic solution, it is ideal for homeowners who would like to get the basics of hydroponics, without the complexity, before going on to developing their skills and applying them to more complex methods, like,
the above mentioned, and them even more complex like, Drip, Aeroponic and Nutrient Film Technique (NFT).
Wick systems are static systems, they have no moving parts, for the beginner, this makes them more practical, cheaper to maintain and a more forgiving active system for hydroponics.
They have a slight drawback in that they are less efficient, and cannot accommodate high maintenance plants, or large plants, which consume a lot of water (e.g. tomatoes), but they are ideal for lettuce or herbs like rosemary and thyme.
The system means the roots are always in contact with the water, the plants are submerged in a grow tray, a non organic soilless additive like horticultural perlite prized for its water absorption capabilities (horticultural perlite is a volcanic glass SiO2, mined globally, with a high
content of amorphous volcanic glass, perlite has considerable expansion properties when heated) can be used.
Caution should be taken with perlite, it can cause fluoride burn on plants, and this is visible as browning of the tips of the leaves. To ensure there is no risk of dust entering your respiratory system use eye, mouth and hand protection when
mixing the formulation and seeding
The grow tray sits on the above level containing the water medium, and is filled up, the seedlings can be transferred directly into the perlite formulation i.e. (perlite and vermiculite) this formulation is probably the best as it does not drain to quickly. It also enables the capillary action of the wicks to be most effective,
without becoming damp and soggy.
The reservoir sits below the grow tray and is large container of nutrient and fertiliser rich water. The water should be refreshed every week because as the plants
absorb the properties; the water medium becomes less nutrient rich.
The aerator or an aeration stone can be used with an external pump. The stone is submerged in the water, and the external pump feeds air into the stone,
which exists air via bubbles through micro pores, this distributes oxygen through the water. Oxygen is essential for the roots, the growth and the health of the plant.
Traditional oxygenation in gardening and hydroponics can include letting the roots dry out between watering schedules. In the wick setup the roots are not aerated in the same way,
as they are never dried out, therefore, it is essential they stay oxygenated in water.
The reservoir has two or more vertical wicks submerged that rise up and are inserted into the grow tray water medium.
Through a capillary action (the ability for liquids to flow through a narrow space without aid of gravity, or in opposition to gravity)
the water feed the grow tray fro the reservoir. The holes in the tray should be secured with a rubber connector and should be smaller
than the wicks to prevent leakage.
6. What to grow
Most plants can be grown in a hydroponic system, beginners should aim for herbs and vegetables as they grow quickly, require little maintenance and do not need a
huge range of nutrients. Monitor the system and adjust the requirements as you see the plants progressing through the growth cycle. Maintenance free plants are also a
great option for beginners, they allow you to focus on the fundamentals of your system, before moving onto more complex methods and plants, they also enable you to grow
like plants together in the same footprint.
Hydroponic systems are based indoors, so do not benefit from natural sunlight exposure. Garden or external plants are exposed to sufficient sunlight daily (depending on placement),
which greatly enables the process of photosynthesis to work incredibly well. Hydroponic plants require at least 6 hours of sunlight daily, with 12 to 16 being ideal. Hydroponic systems
usually come with light fixtures, but if you are building your own, then, you will have to purchase the components and construct the light fixture feature yourself.
The best lighting for hydroponic systems is a High Intensity Discharge light fixture (HID). They contain High Pressure Sodium (HPS) or Metal Halide (MH). HPS emit an orange light,
which is great for the vegetative state of growth. T5 is a high output fluorescent light ideal for cuttings, plants with short growth cycles and samples, lighting should be on an automatic timer
so it turns on and off at the right time of day and for the right duration depending on the cycle.
7. Room conditions
Another important factor to consider is room conditions. Key considerations, are, room temperature, relative humidity, CO2 levels and air circulation. The ideal relative humidity conditions for a room are between 40%-60%,
any higher can lead to fungal and/or mildew problems. Circulation is also important, as in a room temperature of between 68 and 70 degrees Fahrenheit. Higher temperatures can heat up the water causing rot or even stunting the growth of your produce.
The grow room should provide enough CO2 through the circulation of air. Plants take in CO2 and release O2, and this is an essential cycle to support photosynthesis. Additionally, the more CO2 in the room the faster your plants will grow.
8. Water quality
The ideal water constituent for hydroponics is between pH 5.8 and 6.2. You can use chemicals to adjust the pH levels and monitor the levels to operate in this range. It should be noted that hard water with a high mineral content
(salt, calcium etc.) would not dissolve nutrients as well as soft water with a low mineral content.
A filter can be purchased to filter out the high mineral contents and improve the potential for nutrient dissolution.
Macronutrients nutrients or (fertilizer) are distributable in liquid or dry form, they can also be purchased in an organic or synthetic form.
They all are dissolvable in the water medium to create a nutrient rich formulation that is essential to the sustaining your hydroponic system, as well as being essential to the growth and survival of the plants.
The macronutrients, essential for hydroponic growth are listed below:
10. Nitrogen (N)
Nitrogen is by far the most important element; it is responsible for vegetative plant growth, leaves stems and colours. Nitrogen is also responsible for Chlorophyll formation, proteins used in new cells, amino acids and co-enzymes.
In the early growth cycle prior to fruit bearing or flowering. Nitrogen is used in larger quantities.
Plants lacking nitrogen typically have yellow leaves.
11. Phosphorus (P)
Phosphorus contributes to the DNA of the plant or it’s genetic memory and construction. This is essential for cell division.
It also enables plants to flower, fruit, seed and root. Plants require a larger dose of phosphorus during germination and flowering,
as well as being required in relatively smaller doses throughout the whole cycle of the plants growth. Phosphorus deficiency includes shorter plant growth,
fragile leaves, flowers and roots.
12. Potassium (K)
Potassium is required in large doses an is one of the essential macronutrients, it does not form compounds but is required to facilitate photosynthesis,
starch formation, protein synthesis and enzyme activation. Plants in need of potassium display yellow leaves in the initial cycles.
13. Calcium (CA)
Calcium is required for cell formation, development and growth in the plant. Not enough calcium results in the leaf edges turning brown,
whereas too much calcium in the earlier phases can stunt the growth of the plant.
14. Sulphur (S)
Sulphur is a structural component of 2 essential amino acids, Methionine and cysteine. They create proteins,
which help in the activation and formation of certain enzymes and vitamins.
15. Magnesium (Mg)
Magnesium is a chemical component of chlorophyll; magnesium facilitates the creation of oxygen through photosynthesis and is used in large amounts in fast growing plants.
Micronutrients are required but in smaller quantities or in trace amounts include,
iron (Fe), manganese (Mn), boron (B), zinc (Zn), copper (Cu), molybdenum (Mo), and chlorine (Cl).
17. Good starter plants
If you are a beginner to hydroponics, then some examples of good starter plants include:
- Greens like lettuce, spinach, swiss chard, and kale
- Herbs like basil, oregano, thyme, and mint
- Hot peppers
Gillian from Wimbledon, has a hydroponic garden, she was able to find someone ato help her source the materials and kits for a hydroponic garden locally on https://billntrade.com She said,
‘Martin was an indoor garden expert who I found he was able to introduce me to the basics of hydroponic gardening for my property, now I am sell on my way to more crop and am sharing the platform and Martin
services with friends and family’.
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