Hydroponics DIY Guide

Introduction to Hydroponics

Imagine growing lush, healthy plants without a speck of soil in sight. That's the magic of hydroponics, a revolutionary method of cultivation that's taking the gardening world by storm. At its core, hydroponics is all about growing plants in nutrient-rich water instead of traditional soil.

In a hydroponic system, plants thrive in a carefully controlled environment, their roots submerged in a water-based solution packed with all the minerals they need to flourish. Some setups suspend the roots directly in this nutrient soup, while others use inert materials like perlite or gravel to provide support.

As we face the challenges of climate change and its impact on traditional agriculture, hydroponics offers a glimpse of a more sustainable future. It's a method that allows us to grow food in controlled environments, potentially shielding our crops from the whims of an increasingly unpredictable climate.

In the following sections of this guide, we'll dive into the nitty-gritty of setting up your own hydroponic garden at home. Whether you're a curious beginner or a green-thumbed enthusiast looking to expand your horizons, you'll soon discover the joy of watching your plants thrive in their own liquid paradise.

Pros and cons of Hydroponics over Soil based cultivation

One of the most compelling advantages of hydroponics is its incredible water efficiency. Traditional farming can be quite thirsty, but hydroponic systems sip water in comparison. To put it in perspective, growing a kilogram of tomatoes hydroponically uses only about a third of the water required by intensive farming methods. In a world where water conservation is increasingly crucial, that's a game-changer.

But the benefits don't stop there. Hydroponic crops often outperform their soil-grown counterparts in terms of biomass and protein production, given the same environmental conditions and nutrient supply. This efficiency makes hydroponics a promising solution for food production in harsh environments or areas with limited water access – it might even play a role in feeding future space explorers!

The beauty of hydroponics lies in its versatility. From juicy tomatoes and crisp lettuce to fragrant herbs and even medicinal plants, this method can nurture a wide variety of crops. 

While hydroponics offers many benefits, it's not without its challenges. One of the main drawbacks is the initial setup cost. Hydroponic systems require specialized equipment like pumps, lights, and nutrient solutions, which can be expensive to purchase and install. This higher upfront investment can be a barrier for some aspiring hydroponic gardeners.

Additionally, hydroponic systems rely heavily on technology and electricity. This dependence means that power outages or equipment failures can quickly become critical issues, potentially leading to crop loss if not addressed promptly. It also makes hydroponics less suitable for areas with unreliable power supplies.

Hydroponic systems are also more vulnerable to certain issues. For instance, waterborne diseases can spread rapidly through the shared nutrient solution, potentially affecting all plants in the system. This risk requires vigilant monitoring and quick action to prevent widespread crop loss.

It’s always better to understand and be aware of the challenges alongside the benefits before embarking on your hydroponics journey.

Types of Hydroponic Systems

As hydroponics has evolved, several distinct systems have emerged, each with its own unique approach to delivering nutrients to plants. Let's explore some of the most popular methods:

1. Nutrient Film Technique (NFT): 

In NFT systems, a thin film of nutrient-rich water continuously flows over the plant roots. The plants are housed in channels or tubes with a slight tilt, allowing gravity to move the water from one end to the other. This method ensures roots receive a constant supply of oxygen and nutrients. NFT is great for leafy greens and herbs but may struggle with larger, heavier plants.

1. Deep Water Culture (DWC):

DWC, also known as the reservoir method, involves suspending plant roots directly in a nutrient solution. The plants are typically held in net pots above the water, with their roots dangling into the solution. An air pump oxygenates the water, preventing root rot. This system is simple to set up and maintain, making it popular among beginners.

1. Wick System:

The wick system is perhaps the simplest form of hydroponics. It uses a wick, often made of rope or felt, to draw nutrient solution from a reservoir up to the plant roots. The growing medium, which could be perlite, vermiculite, or coconut coir, surrounds the roots and is kept moist by the wick. While very low-tech, this system is limited to smaller plants with low water needs.

1. Ebb and Flow:

The Ebb and Flow system, also called Flood and Drain, uses a timed pump to periodically flood a grow tray with nutrient solution from a reservoir below. After soaking the plant roots and growing medium, the solution drains back into the reservoir. This flooding and draining cycle provides both nutrients and oxygen to the roots. It's versatile, accommodating various plant sizes, and efficient in its use of water and nutrients. While relatively easy to set up, it does require careful timing and monitoring to prevent over or under-watering. The Ebb and Flow system is popular for its balance of simplicity and effectiveness.

1. Drip System:

Drip systems use a network of tubes to deliver nutrient solution directly to each plant's base. A timer controls a pump, which pushes the solution through the tubing. This method allows for precise control of nutrient delivery and can be easily scaled for larger operations. It's versatile enough for a wide range of plants but requires regular maintenance to prevent clogging. The excess nutrient is drained back to the tank via a drain pipe. This way no nutrients are wasted. 

1. Aeroponics System:

Aeroponics takes hydroponics to the next level by misting plant roots with nutrient solution rather than submerging them. The roots hang in air-filled chambers and are periodically sprayed with a fine nutrient mist. This method provides excellent oxygenation and can lead to faster growth, but it's also one of the more complex and expensive systems to set up and maintain.

1. Kratky Method:

The Kratky method is a passive hydroponic technique that doesn't require electricity or pumps. Plants are placed in containers with their roots partially submerged in nutrient solution. As the plants grow and the water level drops, an air gap forms, providing oxygen to the roots. This low-tech approach is great for beginners and works well for leafy greens and herbs.

Each of these systems has its own strengths and is suited to different types of plants and growing conditions. As you delve deeper into hydroponics, you'll find that the best system for you depends on factors like the plants you want to grow, the space you have available, and how much time you can dedicate to maintenance.

System we Chose

We decided to go with a Dutch bucket recirculating drip system. 

The Dutch buckets offer about 20 liters of volume with about a 2L reservoir before draining. 

There are primarily 2 types of drip feed systems that are used in hydroponics. Recirculating and Drain To Waste. 

These 2 systems are popular among commercial growers as they provide a stable system for growing a wide variety of fruiting and vining crops. The Drain to waste system is more popular in commercial environments as it offers quick adjustments to the nutrient solution allowing growers to boost yields and plant growth. This however uses significantly more water and was the reason we went with a recirculating drip system that drains the excess nutrient back into the nutrient tank to be used again for the next drip cycle. 

Nutrients

The pants will require all the nutrients it naturally pulls up from living soil to be added in the nutrient solution. In hydroponics we don’t rely on natural biological processes that breakdown added organic matter in the soil into plant available nutrients. Instead the plants are provided all the necessary nutrients by dissolving them in water and delivering that nutrient rich water to the roots directly. This gives us greater control on the inputs that go into the plants and allows us to quickly adapt and adjust the nutrient solution based on  the needs of the plant. 

Plant nutrients are broadly broken down into 3 major categories. 

1.  Basic Nutrients 

2.  Macronutrients

3.  Micronutrients

Basic Nutrients 

Basic nutrients are primarily freely available to the plant through transpiration and respiration. These would be Carbon, Oxygen Hydrogen. These basic elements are extracted from water, carbon dioxide and atmospheric oxygen.

Macronutrients 

Macronutrients are the primary nutrients that the plant needs in large quantities to perform basic functions like photosynthesis and metabolism. 

Nitrogen is probably considered the most important primary nutrient for plants as it is the key element responsible for photosynthesis. 

Phosphorus is the next nutrient that is considered primary as it contributes to the formation of the DNA and is essential for cellular activities. It plays a critical role in the formation of fruits, flowers, and roots. 

Potassium is the third key nutrient required for plants and although it does not form elements in plant bodies, it  plays a key role in photosynthesis, starch formation, protein synthesis, and enzyme activation.

Calcium, Magnesium and Sulphur are the secondary macronutrients that are essential for activities like cell development, synthesis of chlorophyll and creation of various enzymes essential to plant growth flowering and fruiting. 

Micronutrients

Micronutrients, although not required in large quantities for the plants, are essential to plant growth and fruiting. These nutrients are usually present in trace amounts and some of them although not water soluble are made available to the plant in a chelated form. The major micronutrients are Zinc, Boron, Iron, Manganese.

We strongly recommend that as a beginner or even as a small scale producer you stick to buying off the shelf nutrients that are usually available in a 2 or 3 part system. 

Generally the first part will be Nitrogen heavy and also include most trace nutrients, the second and third part usually are salts of Potassium and Phosphorus. 

Most off the shelf nutrients are available either in a liquid concentrate or as a powder. The liquid form is generally more expensive and will yield less prepared nutrient solution than the powdered form but both work equally well. Follow the manufacturer instructions for preparing the nutrient solution. 

pH Levels

Plant roots absorb different nutrients at different rates depending on the pH of the root zone. Ideally plant root zones should be maintained between a pH of 5.5 and 6.7. pH is a measure of how acidic or basic something is. 7 is considered neutral and anything with a pH lower than 7 is considered acidic and if it has a pH above 7 its a base. 

pH can be adjusted by adding pH up or pH down which is added a few drops at a time to lower or raise the pH of the solution. It is critical that the pH of the nutrient solution is monitored frequently and adjusted as needed.

As the plant uptakes nutrients the pH of the solution will naturally rise as nutrient update happens by ion exchange and as the plant uptakes nutrients it lowers the acidity of the nutrient by exchanging Hydrogen ions. 

Tips

• Use an EC or TDS metre to test the nutrient solution frequently and adjust nutrient levels once a week

• Use a pH probe or pH strips to monitor pH daily and adjust within range. 

• Be conscious of plant spacing, limit the number of plants per bucket to two at the most 3 small plants. Larger plants may be better off one per bucket. 

• Prune your plants regularly, remove old diseased leaves or leaves that are creating poor airflow through the plant. 

• Remember that the nutrient solution is acidic, slightly corrosive and heavy in salts. This means you should avoid it coming into direct and frequent contact with metal surfaces. Ensure the pipes and fittings you use are not made of metal, are non toxic and  UV stable as volatile or unwanted compounds may leach into the nutrient solution and inadvertently get uptaken by the plants. 

• Keep an eye out for pests and disease, although hydroponically grown plants are healthy and free from soil borne pests and parasites the environment also plays a role and you should regularly inspect leaves, fruit and flowers for signs of disease and pest damage. 

• Time your irrigation cycle so that your medium is never completely dry and nutrients are replenished often. You should at the same time ensure the roots are getting ample oxygen as this is vital for plant survival in a hydroponic system. 

• Trellis your plants to give them support, improve airflow and access to light. 

Conclusion

Hydroponics offers a forward-looking solution in the fight against climate change and its impact on global food systems. As the effects of climate change intensify, traditional agriculture faces increasing challenges. Extreme weather events, shifting growing seasons, and water scarcity all threaten to disrupt the food supply chain. By growing plants in controlled environments, hydroponics can help mitigate these risks, providing a stable and reliable source of food even as outdoor growing conditions become more unpredictable.

One of the key benefits of hydroponics is its potential to improve food resilience and yield. Because hydroponic systems can be set up almost anywhere, including urban environments and areas with poor soil quality, they allow for decentralized food production. This decentralization reduces the need for long-distance transportation, cutting down on carbon emissions and making food supply chains more robust against disruptions. Additionally, hydroponic systems can be optimized for year-round production, resulting in higher yields compared to traditional soil-based farming.

As climate change continues to challenge the viability of conventional agriculture, the need for food resilience becomes more pressing. Small pockets of community-grown hydroponic gardens can play a crucial role in building local food security. By growing food closer to where it is consumed, communities can reduce their dependence on large-scale industrial agriculture and create more sustainable, self-sufficient food networks. This is especially important in regions where good quality soil is becoming increasingly rare, leading to lower yields and poorer-quality produce in traditional farming.

In summary, hydroponics is not just a method of growing plants—it's a tool for building a more resilient and sustainable food system. By embracing hydroponics, we can address some of the most pressing challenges of our time, from climate change to food insecurity, and ensure a healthier, more sustainable future for all.