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Education

At Greentopia Japan, we offer a wide range of educational programs designed for children, adults, and communities.

Using our innovative hydroponic towers, these programs teach participants not only how to grow food without soil but also integrate valuable STEM learning opportunities.


Through engaging experiments, students discover how plants grow, what they need to thrive, and what makes them nutritious and delicious. They also learn how hydroponic farming supports sustainability goals—whether for schools, businesses, or personal use—and how it contributes to the fight against climate change.

Supplement your school's extracurricular offerings with the Green STEM Club. With the use of a hydroponic tower included, we'll  discuss everything from plant biology, sustainability, ecology, nutrition, and much more!

After School

Green STEM Club

Price: ¥4,000 (per student per session)

Period: 8-14 weeks

Minimum 8 students

Please contact us for more details!

Greentopia can run classes during school hours, or help supplement an existing program with a focus on hydroponic growing and/or urban farming. Whether your goal is to start a food garden for your school or to launch a sustainability initiative,  we are ready to help! Inquire for a custom-prepared program that suits your educational goals and time constraints! 

In-School

Programs

¥12,000-20,000 per session

Minimum 6 students

Please contact us for more details!

  • Hydroponics is a method of growing plants without soil, using a water-based solution enriched with essential nutrients. In this system, plants receive their nourishment directly from the nutrient-rich water, enabling them to grow in virtually any environment, such as in greenhouses, on rooftops, or even indoors. Hydroponics allows for the efficient use of water and space, and often results in faster plant growth and higher yields compared to traditional soil-based agriculture.

  • A lot! Leafy greens like lettuce, spinach, and kale are popular choices due to their quick growth cycles and minimal space requirements. Herbs such as basil, mint, cilantro, and parsley also thrive in hydroponic setups, offering fresh flavors that will give zip to your dishes. Vegetables like tomatoes, cucumbers, peppers, and strawberries can produce abundant yields under controlled hydroponic conditions. Even root crops like carrots and radishes can be adapted to certain hydroponic systems with deeper growing media. Essentially, most plants that can be grown in soil can be adapted to hydroponic systems, with the right care and conditions.

  • Organic farming traditionally requires soil cultivation, emphasizing the natural decomposition of organic matter into nutrients through a process known as mineralization. This method is essential for a crop to be considered organic, as it involves natural microorganisms converting organic matter into essential minerals like nitrogen, phosphorus, and potassium without synthetic chemicals.
     

    However, our hydroponic technology, while not officially organic since they bypass soil cultivation, achieves remarkable environmental efficiencies. We use up to 99% fewer pesticides, 95% less water, and 90% less space compared to traditional organic farming, and our crops boast nutrient densities comparable to or exceeding those grown in soil. Despite these advantages and our adoption of practices such as using organic seeds and organic pesticides, the lack of soil in our system means we cannot be certified as organic under current definitions. As a result, we describe our approach as "Beyond Organic", reflecting our commitment to sustainability and high nutrient levels in our produce, even as we challenge conventional organic certification criteria.

    1. Water Efficiency: Hydroponics uses significantly less water compared to traditional soil farming, as the system recirculates water, leading to savings of up to 90% in water use.
       

    2. Space Savings: Hydroponic systems can be stacked vertically, dramatically reducing the amount of land needed for growing crops. This makes it ideal for urban areas or places with limited agricultural land.
       

    3. Faster Plant Growth: Plants in hydroponic systems can grow faster since they receive a perfectly balanced amount of nutrients directly in the water solution, without having to search through the soil.
       

    4. Reduced Pests and Diseases: With no soil, there's a lower risk of soil-borne pests and diseases, which can reduce the need for pesticides.
       

    5. Year-Round Growing: Hydroponics allows for controlled indoor environments, meaning plants can be grown year-round, regardless of outdoor weather conditions.
       

    6. Accessibility: Hydroponic systems can be set up almost anywhere, providing fresh produce even in areas with poor soil quality or harsh climates.
       

    7. No Weeding: Without soil, there's no need for weeding, making hydroponics less labor-intensive.
       

    8. Controlled Nutrition: Nutrient levels can be precisely controlled, optimizing plant health and yield.
       

    9. Reduced Transportation Costs: By setting up hydroponic farms near urban centers, the distance food needs to travel from farm to consumer is decreased, reducing transportation costs and carbon emissions.
       

    10. Conservation of Soil: Hydroponics conserves soil by eliminating the need to disturb the land for agricultural purposes.

  • There are several types of hydroponic systems, each with unique features and methods for delivering nutrients to plants:

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    1. Wick System: The simplest form of hydroponics, the wick system uses no pumps or electricity. It relies on a wick to draw nutrient-rich water from a reservoir to the plant roots, which are usually in a growing medium like perlite, vermiculite, or coconut-coir.
       

    2. Deep Water Culture (DWC): In DWC, plants are suspended in a solution of nutrient-rich, oxygenated water. The roots are submerged directly in the water, and an air pump is used to oxygenate the solution, preventing the roots from drowning.
       

    3. Nutrient Film Technique (NFT): NFT systems involve a continuous flow of nutrient solution over the roots of plants, which are held in channels. Only the tips of the roots come into contact with the nutrient solution, allowing the rest of the roots to access oxygen in the air.
       

    4. Ebb and Flow (Flood and Drain): This system works by temporarily flooding the grow tray with nutrient solution at intervals, which then drains back into the reservoir. This process is controlled by a timer and a pump.
       

    5. Aeroponics: In aeroponic systems, plant roots hang in the air and are misted with nutrient solution at regular intervals using a pump and misting nozzles. This system provides excellent oxygenation to the roots.
       

    6. Drip System: One of the most widely used systems in commercial hydroponics, the drip system delivers nutrient solution to the base of each plant through a network of tubes (drippers). The flow rate can be adjusted to meet the needs of different plants.
       

    7. Hybrid Systems: There are hybrid systems that combine features of the above methods to suit specific plants, environments, or grower preferences. For example, a hybrid might use the DWC system for rapid growth during the vegetative stage and switch to an NFT or drip system for the flowering stage.

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    Each system has its advantages and is suited to different types of plants, scales of operation, and grower preferences.

  • Yes, hydroponic plants often grow faster than soil-grown plants. This accelerated growth is due to several factors inherent in hydroponic systems:

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    1. Optimized Nutrient Availability: In hydroponics, nutrients are dissolved in water and delivered directly to the plant roots. This means plants don't have to expend energy developing extensive root systems to search for nutrients, allowing them to grow faster.
       

    2. Controlled Environment: Hydroponic systems typically offer greater control over environmental conditions such as temperature, humidity, and light intensity. This allows for optimal plant growth conditions, minimizing stress on the plants and leading to faster growth rates.
       

    3. Increased Oxygen to Roots: Hydroponic systems, especially those that use aeroponics or deep water culture, provide more oxygen to the plant roots. This enhanced oxygenation encourages faster root growth and nutrient uptake.
       

    4. pH and EC Control: The pH and electrical conductivity (EC) of the nutrient solution can be precisely controlled in hydroponic systems, ensuring that plants receive the ideal balance of nutrients at all times.
       

    5. No Soil-Borne Diseases: Since hydroponics doesn't use soil, there's a reduced risk of soil-borne pests and diseases, which can slow plant growth. This leads to healthier plants that can allocate more energy towards growth.

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    These factors contribute to more efficient use of energy and resources by the plants, resulting in quicker growth rates compared to traditional soil-based gardening.

  • Hydroponics conserves resources in several significant ways:

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    1. Water Conservation: Hydroponic systems are incredibly water-efficient, using as much as 90% less water than traditional soil-based farming. This is because water in hydroponic systems is recirculated, meaning that unused water can be reused by the plants, rather than being lost through soil drainage.
       

    2. Reduced Land Use: Hydroponics allows for vertical farming, which significantly reduces the amount of land needed to grow the same amount of crops compared to traditional agriculture. This can help preserve natural habitats and biodiversity by reducing the need for deforestation and land conversion for agricultural purposes.
       

    3. No Need for Soil: Since hydroponics doesn't use soil, it eliminates the need for arable land. This is particularly beneficial in areas where soil conditions are not conducive to agriculture, or where soil degradation and erosion are major concerns.
       

    4. Lower Fertilizer Use: In hydroponic systems, nutrients are provided directly to the plant roots in the exact amounts required, reducing the overuse and waste of fertilizers. This also minimizes the risk of fertilizer runoff into nearby water bodies, which can lead to pollution and eutrophication.
       

    5. Pesticide Reduction: Hydroponic systems, especially those in controlled environments like greenhouses, often require fewer pesticides than traditional farming methods. This is due to the reduced presence of soil-borne pests and diseases, and the controlled environment which can prevent many common plant ailments.
       

    6. Energy Efficiency: Although hydroponic systems, particularly those indoors, can require significant energy for lighting, pumps, and climate control, advances in technology such as LED lighting and renewable energy sources are making hydroponics more energy-efficient.
       

    7. Reduced Transportation Costs: Hydroponic farms can be established closer to urban centers, reducing the distance food needs to travel from farm to consumer. This reduces transportation-related carbon emissions and conserves the energy associated with long-haul transportation.

     

    By addressing these key areas, hydroponics presents a more sustainable and resource-efficient approach to farming that can contribute significantly to conservation efforts.

  • The essential nutrient requirements for hydroponic systems are carefully balanced and provided directly to the plants' roots in a soluble form. These nutrients are broadly categorized into macronutrients and micronutrients:

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    1. Macronutrients:
       

      • Nitrogen (N): Crucial for leaf and stem growth, nitrogen is a key component of chlorophyll, which plants use for photosynthesis.

      • Phosphorus (P): Important for root development and flower and fruit production, phosphorus plays a role in energy transfer within the plant.

      • Potassium (K): Helps in overall plant health, disease resistance, and the regulation of many physiological processes.

      • Calcium (Ca): Vital for cell wall structure and stability, calcium also plays a role in enzyme activity and response to environmental stimuli.

      • Magnesium (Mg): A central component of chlorophyll, magnesium is essential for photosynthesis and enzyme activation.

      • Sulfur (S): Important for protein synthesis and some plant hormones, sulfur also helps with disease resistance.
         

    2. Micronutrients (Trace Elements):
       

      • Iron (Fe): Necessary for chlorophyll synthesis and functioning as part of many enzyme systems.

      • Manganese (Mn): Involved in photosynthesis, nitrogen assimilation, and the synthesis of some enzymes.

      • Zinc (Zn): Plays a role in growth hormone production and enzyme systems.

      • Copper (Cu): Important for photosynthesis, nutrient metabolism, and as a component of enzymes.

      • Boron (B): Aids in cell wall formation and helps regulate the uptake of other nutrients.

      • Molybdenum (Mo): Vital for nitrogen fixation and nitrate reduction in plants.

      • Chlorine (Cl): Involved in photosynthesis and osmotic regulation.


    The concentration of these nutrients in the hydroponic solution must be carefully monitored and adjusted to meet the specific needs of the plants being grown. The balance of these nutrients is critical; too much or too little of any nutrient can lead to deficiencies, toxicities, and inhibited growth. The pH of the nutrient solution also needs to be managed, as it affects the availability of these nutrients to the plants, with the optimal range typically being between 5.5 and 6.5 for most plants.

  • pH, or the potential of hydrogen, is a scale used to measure the acidity or alkalinity of a solution, with a range from 0 to 14. A pH of 7 is considered neutral, values below 7 are acidic, and values above 7 are alkaline.

     

    In hydroponics, pH is crucial because it affects the plant's ability to absorb nutrients. The nutrient solution's pH can influence the solubility of minerals and nutrients. If the pH is too high or too low, it can lock out certain nutrients, preventing plants from taking them up, even if they are present in the solution. This can lead to nutrient deficiencies, stunted growth, or even plant death.

     

    Each plant species has an optimal pH range that facilitates the best nutrient uptake. Generally, most hydroponic systems work well with a slightly acidic pH range of about 5.5 to 6.5. Maintaining the nutrient solution within this range ensures that plants can efficiently absorb all the necessary nutrients.

     

    Regular monitoring and adjusting of the pH in a hydroponic system are essential for maintaining healthy plant growth. 

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