A Guide To Building An Indoor Hydroponic Garden

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Have you always wanted to grow your own vegetables but don’t have the time or patience for a traditional garden? Or maybe you would like to grow vegetables hydroponically as a small commercial venture! Indoor hydroponics is becoming increasingly popular as an alternative way to get fresh produce year-round or establish a home-based business. We have put this hydroponics guide together to help you get started on your indoor hydroponic system, large or small!

Any hydroponic method can be used to build an indoor hydroponic system. The most versatile and commercially viable method would be to use an NFT hydroponic method or an adaptation of this method that best suits your space. It is easy to manage and has limited potential for damage due to failure.

Building an indoor hydroponic garden is a great way to grow your own vegetables and herbs year-round. Hydroponics can be operated on a small scale in your kitchen, or for larger systems, you can dedicate a room or a basement to your hydroponics or a garage or outside shed. The beauty about hydroponics is that it is scalable, which allows you to start small and work up to a larger scale operation if that is your goal. But you need to start somewhere, so let’s get started on your planning!

How Do You Build An Indoor Hydroponic Garden?

Hydroponics is a method of growing plants in a soil-free system that feeds the plants by supplying them with a nutrient-rich water solution. This is essentially a hydroponics system in its simplicity. The complications come in the delivery of the nutrient-rich solution to the plants.

There are many versions of hydroponics systems, and most of the differences in the various types are in the way the nutrient solution is supplied to the plants to feed them. Each type has its strong points and disadvantages, and some are better for indoor application than others.

Before we get onto the types of hydroponics systems to choose from, we need to investigate some other practical considerations that could have a bearing on the type of hydroponics system that you choose to implement.

Space Considerations For Your Hydroponics

Since we are investigating indoor hydroponic systems, space will be a limitation for the type of system that you eventually settle on as the right system for your circumstances.

You need to scrutinize your available space for your hydroponics system before you choose the system you want to implement since some systems have a larger space requirement than others. There is no point in investigating the systems first, only to find that the one you like won’t fit in your allocated indoor space.

Airflow In Your Indoor Hydroponic Space

Airflow is an important factor for consideration in an indoor hydroponic operation, and it is an aspect that many people forget to give attention to until they experience problems related to this aspect.

Plants need fresh air for their growth and development. If your indoor space for your grow system does not have access to the outside air, you may have to put in extractor fans and ducting to remove stale air and bring in fresh air.

Airflow also helps to control the humidity in the room, which will be elevated due to the amount of water in the hydroponic system and because the plants release water vapor into the atmosphere as part of their respiration process.

Lack of adequate airflow can result in the development of mold and damp problems in your hydroponics room.

In most cases, a room with a window that can be opened will provide enough ventilation to overcome the majority of these problems. However, if you are placing your system in a basement, airflow is an aspect that you will need to give some thought to.

Lack of Pollinators For Indoor Hydroponic Plants

Another factor of plant growing and production of food crops in an indoor hydroponics system that sometimes escapes beginners is the lack of pollinators in your indoor environment to pollinate your plant’s flowers.

If the plants that you intend to plant in your system require insect pollinators to pollinate their flowers, you need to consider how you are going to get this job done in your indoor location that excludes the natural pollinators from your plants.

There are ways to circumvent this pollination problem, such as choosing to grow plants in your indoor system that do not require pollination by insects or learning how to pollinate these plants manually yourself.

This aspect of indoor growing needs consideration before you grow the wrong type of plants and have a less than spectacular harvest from your hydroponic system.

Light Requirements of Plants In Indoor Hydroponics Systems

The basic requirements that a plant needs to grow and produce fruit are nutrients, air, and light. The question of light is the topic you need to give some thought to for your indoor system. All plants need light, but vegetables, in particular, need lots of light.

If you look at the seed packet of most vegetable seeds, you will see that they need between 6 to 8-hours of sunlight per day to produce a good harvest. They need all that energy from the sun to grow and produce fruit that you eat.

In an indoor environment, you need to make sure that you can provide not only the right amount of light but also the right type of light to provide for the needs of your plants.

If your indoor hydroponics room has lots of natural sunlight entering the room for most f the day, you may get away with not needing to provide artificial lighting for your plants. In most cases, even the brightest rooms only have sunlight for a small portion of the day, so it is highly likely that you will need some sort of artificial lighting for your plants.

Select A Hydroponic System

Hydroponic systems are a growing method that has been around for a long time, which is a good thing. It means that there have been many different types and styles of systems developed to suit most indoor plant growing situations. Thus, you should be able to find one of the systems suitable for your requirements for an indoor hydroponic system.

The beauty of hydroponic systems is that once you understand the principles, you can easily develop a custom system or a mixture of different systems that you can customize to suit your space and needs perfectly.

Types Of Hydroponics Systems

There are a multitude of different hydroponic growing techniques, each with its advantages and disadvantages. All of the techniques have application for an indoor system, but some will make more practical use of the space than others.

We will take a look at each hydroponic system type with the indoor application in mind, which will help you to decide which application will fit your space limitations better.

Static Solution Culture

The static solution culture is the simplest of all the hydroponic systems and is hydroponics in its most basic form.

This system uses a container or reservoir which contains the nutrient solution, and the plant is grown in the same container. There is no flow in or delivery system needed for the nutrient solution, and no pumps are required. The system can be aerated or not.

If you do not use an aeration pump to provide oxygen to the water, then you can suspend the plants so that some of the roots are suspended in the air space between the nutrient solution and the top of the container.

The nutrient solution can be replaced or replenished on a set schedule to make sure that the plants receive enough nutrition. The nutrient content can be monitored with the use of an electro-conductivity or EC meter.

Many people start out in hydroponics using this method of growing plants in glass mason jars. The outside of the glass jar should be covered with cardboard to prevent light from entering the nutrient solution and promoting the growth of algae in the system.

This system can work for an indoor hydroponics operation because you can have multiple containers growing different types of plants in different containers that can be located in various positions around your space.

The downside of this hydroponic technique is that when your containers become too numerous, it can be a labor-intensive operation to change the nutrients in each one one by one. For this reason, the static solution method is considered a small-scale technique for growing plants hydroponically.

Wick Hydroponic Systems

Wick systems, or wicking systems as they are sometimes called, are also considered to be a basic or entry-level hydroponic technique.

In the wick technique, the plants are grown in a growing medium in a tray that is suspended above the reservoir containing the nutrient solution. The solution of nutrients is delivered to the plants by means of a wick in the form of a piece of natural fiber rope or felt.

One end of the wick is embedded in the growing material the plants are in, and the other end dangles in the nutrient solution below.

The nutrient solution makes its way up the wick by means of the wicking action, and it is delivered to the growing medium where it is accessible to the plants.

This type of hydroponics system is called a passive system because there are no mechanical or moving parts to deliver the nutrients to the plants. This is an advantage where electricity is unreliable or non-existent, but the system has limitations.

The main limitation of the wick system is that it can only accommodate small plants. Plants that grow big or that have a high water demand will use up the nutrient solution faster than the wicks can deliver the solution.

The wick system is not recommended for your indoor hydroponics system because it is extremely limiting in the both the type and size of plants that you can grow in this system. You will soon become frustrated with this method and look to implement a new solution.

Dutch Bucket Hydroponic Systems

The Dutch bucket consists of a bucket that houses the growing medium, which must be a medium that holds moisture well. The most popular medium types are coir hair from coconuts, perlite, and vermiculite. The plants are planted in this growing medium and provide the support needed for the root system.

In the system, you also have a separate reservoir that contains the nutrient solution. A pump is used to deliver the nutrient solution to the top of the Dutch bucket, where it percolates down through the growing medium where the plants can use it.

There is a drain that is fitted near the bottom of the bucket that will return unused nutrient solution back to the reservoir. Gravity is used to deliver the excess nutrients back to the reservoir, so the buckets need to be mounted higher than the nutrient reservoir.

There are some disadvantages to the Dutch bucket system that may limit the capacity of your indoor hydroponic growing capability.

  • Best for smaller plants. The Dutch bucket is usually limited to having one or two plants per bucket. In some cases, with small plants such as leaf lettuce, you may be able to increase this to 3 or 4 plants.
  • Not suitable for larger plants. While you can plant larger plants in this system, such as tomatoes, peas, and beans, and you can trellis them vertically, you will only be able to plant one of these plants per bucket.
  • Not very space-efficient. The dutch bucket system works well, and the plants grow strongly in this system, but the buckets can take up a significant amount of space, and not being able to grow many plants in each bucket will restrict your growing volume in your indoor space.

While the Dutch bucket system is a great hydroponic method, these disadvantages make it generally unsuitable for an indoor hydroponic growing system unless you have a lot of indoor space available to house the buckets and reservoirs.

There are other hydroponic methods that make better use of space and are thus more suitable for a high volume indoor production. However, if you are starting out in hydroponics and only want to grow some food crops for your family, then the Dutch bucket system is a great way to start.

Deep Water Culture Hydroponic Systems

The deep water culture or DWC hydroponics system is a method that is often used by high-volume commercial growers because of its simplicity.

The main benefit of the deep water culture system is that there is no delivery system for the nutrients, which eliminates a point of failure in the system.

The plants are grown directly in the nutrient solution, usually supported on a float that is floating directly on the surface of the nutrient solution. The float has holes in it, and the plants are supported in baskets that fit in the holes, with the roots of the plants being directly in the solution beneath.

Because the roots of the plants are directly in the nutrient solution, the nutrient solution needs to be aerated to provide enough dissolved oxygen for the plants since there is no air space in the system for the roots to get air.

The aeration is normally provided by means of an air stone connected to an electric air pump, which bubbles air through the water. It is a similar system to what is used to aerate the water in an aquarium.

The main advantage of the deep water culture system is that it is relatively inexpensive to get set up and running, and it is easy to manage and maintain.

The main disadvantage of the DWC hydroponics system, particularly in relation to an indoor system, is that it uses a lot of space. You need containers with large water surfaces to grow a sufficient number of plants, and this can take up too much space in a small indoor location.

Ebb And Flow Hydroponic Systems

The ebb and flow hydroponics systems are sometimes also referred to as flood and drain systems. The concept behind this method of hydroponics is that the grow chamber where the plants are housed is flooded periodically with nutrient solution, and it drains out through the grow medium back in the reservoir.

This system has a separate grow container and nutrient reservoir. A pump is used to pump the nutrients from the reservoir to the grow chamber up to a particular level. The pump then switches off, and the nutrient solution slowly drains through the growing medium and eventually flows out of an overflow pipe back to the reservoir.

This process is similar in concept to the Dutch buckets, except the Dutch bucket system has a constant flow of nutrient solution.

The advantage of this type of hydroponics system is that the pump switches off when the nutrient solution reaches a particular level in the growing container. This reduces wear and tear on the pump.

The downside to ebb and flow hydroponics is that the system introduces more complexity and more equipment that has the potential to go wrong. The pump must be run on a timer that is set precisely to deliver the right amount of nutrient solution at the right time.

If the timer fails, the plants could be starved of nutrients, and the roots can dry out, potentially causing the plants to die.

An ebb and flow hydroponics method is not suitable for an indoor hydroponics operation unless you have the time to put in the effort to dial the system in perfectly with the timing of the ebb and flow. The system also needs to be more closely monitored for the breakdown of any of the components in the system.

Nutrient Film Hydroponics Systems

The nutrient film technique or NFT method of hydroponic implementation is a combination of ideas from DWC and ebb and flow methods of hydroponics.

The NFT system has a reservoir and a separate growing container for the plants. The growing container has holes in the top that support the plants in a growing basket that is filled with a growing medium such as coconut coir, or in some cases, no growing medium at all.

The plants’ roots extend down to the level of the nutrient solution in the grow chamber. Some of the roots are in the air, and some are submerged in the solution.

The growing chamber is normally installed at a slant, which promotes the flow of nutrients to an outlet pipe at the opposite end to the inlet pipe for the nutrient solution.

The outlet pipe directs the overflow back to the nutrient solution reservoir. The system can be set up that even when a pump stops running, there is enough nutrient solution in the grow container that the plants can survive for a day or two without suffering any ill effects. This means that the outlet pipe is raised so that the grow container does not drain completely as it does in an ebb and flow system.

The NFT method of hydroponics is flexible and can be set up in many different configurations, which makes it the best hydroponics method for an indoor hydroponics system. The system can be set up to use wide trays as the grow chamber or lengths of PVC pipe.

If you use the PVC pipe method, you can layer the pipes to have plants growing in a vertical system to maximize your use of your indoor space. You can even build the pipes into a framework on casters or wheels that you can move around in the space to maximize the use of natural light in the room.

Drip Hydroponic Systems

There are two main types of drip hydroponic systems; recovery drip systems and non-recovery drip systems.

Essentially, the drip hydroponics system has a growing container where the plants are grown and a reservoir for the nutrient solution. The nutrients are delivered to the plant container by means of a pipe system that delivers the nutrients to the plants by means of drippers connected to the pipes at intervals that correspond to the spacing of the plants.

The drip system can be fed by a pump or by gravity feed, which gives some versatility to the system and makes it an option where electricity is not available or the supply is erratic.

If the system includes a drainage system that drains excess nutrient solution back to the reservoir, then it is termed a recovery drip system. If there is no return route for the nutrients, then it is a non-recovery drip system, and the drip rate is controlled to limit the amount of nutrients releases to prevent the plants from becoming waterlogged.

The drip hydroponic system is a versatile system and can be implemented as an indoor hydroponic system very successfully, but it can be fairly expensive to set up. The piping and the drippers can add up, and the drippers can clog up and need to be replaced, which adds to the ongoing expense.

If you choose the drip hydroponic method for an indoor hydroponic system, it is recommended that you implement it as a non-recovery system to enhance the simplicity of the system.

Select A Hydroponic Grow Medium

The selection of your growing medium in which to grow your plants will largely be determined by the type of hydroponics system you decide you use.

Coir works well in NFT, DWC, and ebb and flow systems, but for dutch buckets and wick systems, a medium such as perlite or vermiculite would be the better choice.

Select The Nutrient Type

The nutrient type that you select for your system will depend heavily on what is available in your area. The good news is that most nutrient types can be used in any of the hydroponics systems we have mentioned.

With most of the nutrient solutions, you will need to adjust the concentrations of the types of nutrients depending on the plant and the stage of development the plant is in. Winter and summer plants also require different concentrations of the various nutrient types.

The important aspect is that once you start with a particular brand or nutrient solution method, you don’t change nutrient brands or systems in the middle of a growing cycle. Rather wait until you are ready to plant a new batch of plants in your hydroponics system.

General Hydroponics is a trusted brand of hydroponic nutrients that has a product for most types of plants that you would want to grow in a hydroponics system.

Fox Farms and TPS are other recommended brands that supply good quality nutrients to use in your indoor hydroponics system.

Is indoor hydroponics profitable?

Indoor hydroponics can easily expand from a personal hobby to a profitable business that can bring in an additional income for you and your family.

Indoor hydroponics is a profitable operation because you can grow a high volume of plants in a relatively small space. The plants also grow faster and produce a harvest faster than when they are grown in the soil, which allows a faster turnaround to harvest to meet the demand for your product.

If you start an indoor hydroponic system, you will quickly find that the proliferation of growth in your plants will quickly outstrip what you and your family can consume. Your next problem is what to do with the excess. At this point, you can consider selling your excess products and turn your hydroponics hobby into a profitable business.

Conclusion

The best indoor hydroponic system would be a system that is based on the NFT method of hydroponics. This system will give you the greatest flexibility for configuration that is adaptable to the indoor space that you have available.

Any of the systems we have mentioned can be used successfully for an indoor hydroponics system, especially if you are only growing plants for your and your family’s needs. However, if you want to make your hydroponic system profitable, you will need to grow a higher volume of produce in the same space.

The NFT system is perfect for growing a large volume of pants in a limited amount of space and would be the hydroponic system of choice for this type of operation.

References

https://www.gardeningknowhow.com/garden-how-to/propagation/propgen/dutch-bucket-hydroponics.htm

https://sensorex.com/blog/2019/10/29/hydroponic-systems-explained/

https://www.simplyhydro.com/system/

https://hydropros.com/blogs/growers-corner/6-types-hydroponic-systems

https://www.gardeningchores.com/types-of-hydroponic-systems/

https://www.squaremilefarms.com/post/how-to-build-your-own-hydroponic-system-a-beginners-guide

https://en.wikipedia.org/wiki/Hydroponics

https://www.amazon.com/s?k=General+Hydroponics&ref=bl_dp_s_web_3029221011