There is a wide selection of plants that you can grow via the aquaponics technique. From simple spices to fruit-growing shrubs, aquaponics can help you produce aesthetically pleasing and natural-grown fruits and vegetables.
However, before you start planting, there are a few things to think about. Consider that some plants flourish in smaller systems, but nutrient-hungry plants need larger systems to thrive. Continue reading to find out which plants thrive in an aquaponics system, as well as the best type of aquaponics approach for your favorite greens.
What is aquaponics?
Most of us are aware of how conventional farmers grow our favorite fruits and vegetables. In a typical form of gardening, seeds are planted in the soil. When they germinate, growers apply water and fertilizer as needed, eliminate weeds and insects, then wait to see if the plant thrives.
However, hydroponics takes a radical approach by eliminating the soil medium in growing the plants. Instead, plants are cultivated in water that contains nitrates which plants use as nutrients for their growth and development.
An aquaponics system takes the hydroponics concept a step further and operates by producing a nitrogen cycle in the water that fish and plants symbiotically share.
First, fish wastes in the fish tank are rich in ammonia. The waste is cyclically carried into the grow bed by the pump, where when drained and exposed to oxygen, bacteria convert it to nitrites and eventually to nitrates. These nitrates provide nourishment for the plants, and in exchange, the plant roots clean the water in the grow beds before returning it to the fish tank. Here the cycle begins again.
Not only do the plants need the fish waste as nutrients, but ammonia and nitrate are toxic to fish, and without the plants, as a biofilter, the fish would die in a closed system from their own excrements.
As you can see, in an aquaponic system, water and nutrients are recycled in a closed-loop system, which is frequently more efficient than traditional soil farming.
What factors should I consider in aquaponics?
Preferred aquaponics system
Three designs are available for anyone who aims to use aquaponics to grow their favored plant products. These are Nutrient Film Technique, Deep Water Culture, and Media Bed.
- Nutrient film technique - Growers also call this by its acronym, NFT. This method is best applied for leafy greens and is most popular with hydroponic farming. Because of their space-saving feature and lower labor costs, NFT systems are popular in the commercial sector. Crops can also be grown vertically (or on a shelf), making them more accessible, space-efficient, and harvestable.
- Deep water culture - This technology, also known as raft or float systems, involves suspending plant roots in nutrient-rich, aerated water using floating rafts. The plant roots float immediately into a 1-foot deep pool of water. Filtration mechanisms must be included in the design because there are no media to capture and process the solid wastes. As a result, more advanced aquaculture techniques and system requirements are required, resulting in considerable initial expenses.
- Media bed - Aquaponics in the media bed method employs containers filled with rock media such as gravel or expanded clay to support plant roots. The bed is inundated and drained with nutrient-rich water to provide the plants with the nutrients and oxygen they require. The media used to support the plants serves as both a mechanical and a biofilter to capture and break down wastes.
Type of plants
Various plants work perfectly with the types of aquaponics mentioned above.
- Edible crops - The most popular plants grown in aquaponics systems are edible crops. Edible plants grow quickly; however, this varies depending on whether you grow annual or perennial crops.
- Ornamental plants - Cut flowers account for most ornamental aquaponics commercial sales, but they are not the only alternative for production. You can sell them directly to customers after culturing nursery stock and even houseplants from seed or cuttings in an aquaponics system.
Fish species
You can keep a large variety of fish in your aquaponics tank. In a closed system, a large number of fish can live and thrive. Considering weather conditions and legality, I recommend you to look into the best fish for aquaponics accessible in your location.
Environment
To produce a healthy plant, the amount of sunlight, temperature, and rain must be considered. Choose a variety of edible crops or ornamental plants that will thrive in your climate if you choose to grow them outside.
You can always grow in a greenhouse or indoors, but you need to locate plants that thrive in low or artificial light. It is ideal to choose a plant that flourishes in your environment, as this will reduce the amount of electricity required to keep your system running.
What are the essential components of aquaponics systems?
The components that comprise any aquaponics system, regardless of the technique you will adapt, are biotic and abiotic.
Biotic components - These are the living organisms that thrive in aquaponics. Fish, plants, and bacteria compose the biotic feature of the aquaponics setup.
- Fish - This is the aquaponics system's aquaculture component. The fish excretions eventually provide the nutrients required to grow the plants. Because they are live animals, the fish tank is the part that requires the most attention. They even serve as significant markers of the system's general health. When choosing fish, several criteria must be considered, especially when kept in a tank setting. The fish must be able to live in high-density population settings to achieve maximum growth output.
- Plants - The aquaponics system's primary objective is to cultivate plants in an environmentally sustainable manner while also achieving food security. The plants are not the only ones who benefit from the aquaponics system. They serve a crucial part in keeping the aquaponics system's overall cycle running smoothly. They operate as a natural water filter, collecting nitrates and purifying the water, allowing it to be recirculated back to the fish.
- Bacteria - Between the fish and the plant stage are the bacteria. These microorganisms are responsible for converting waste into nutrients that plants can take. The nitrification process accomplishes this.
Abiotic components - On the other side of the spectrum, the abiotic components are the non-living factors present in aquaponics.
- Fish tank - You will cultivate your preferred fish in the fish tank. It will also store fish effluents to be processed into a form that the plants may use. The tank will be your primary priority, and you will need to consider its size, durability of materials, and the effort you will put into maintaining it. You can purchase a tank as small as an indoor aquarium or as large as you want it to be. Ready-made containers are available in various sizes, including popular options such as in-home aquariums, backyard ponds for Koi, food-grade barrels, and IBC totes.
- Grow beds - Another crucial consideration in setting up an aquaponic system is the grow beds. These beds will confine your plants as well as the nitrate-rich water they require to thrive. Darker grow beds are commonly used since they block light from reaching the roots and limit algae growth. The size of the beds will depend on the amount of space available and the number of plants you wish to cultivate. Consider vertical systems, in which grow beds are stacked on top of each other to enhance the number of plants you can produce. Floating beds that do not require additional pipes or pumps can also be used on top of the fish tank.
- Piping - The tubes in your aquaponics system help transport the water from the fish tank to the growing beds and back to the fish tanks. Plumbing is necessary whether you plan to employ media beds or NFT since it moves water across your system to promote growth. The key concept is to arrange the pipes so that you may pump up water, distribute it to the beds or allow it to run through your channels, and then return it to the fish tank. The majority of the pipes used in aquaponics are constructed of PVC. PVC pipes are available in a wide range of diameters all around the world. They can be cut and bent because they are easy to deal with. More importantly, PVC pipes are long-lasting, lightweight, and sturdy.
- Pumps - Water pumps are essential for ensuring that the water in an aquaponic system circulates appropriately to maximize the system's efficacy. Their primary function is to distribute the water so that both plants and fish acquire the nutrients they require. A water pump can be regarded as the heart of the entire aquaponics system, while water could be the blood that flows through the system and gives necessary nutrients to all living organisms.
- Water - The aquaponics system would never be complete without the water which the fish and plants need. According to an online article published by the New Mexico State University, "Selecting the source of water used in an aquaponics system can greatly influence the water quality, and is an important first consideration." Aquaponics' potential water sources include rainwater, municipal water, wells and springs, rivers, creeks, streams, lakes, and ponds. Regardless of the source, you must look into the water's pH level, chlorine presence, and hardness.
What factors must I consider in choosing plants for aquaponics?
Deciding which plant should you grow in your aquaponics project might present a certain degree of difficulty considering that wide selections are available today. At this point, here are some guidelines that will aid you in choosing the appropriate plants you should try for aquaponics.
- Identify your purpose for aquaponics. This factor helps you to choose whether to grow commercially, for beautification, or for the sake of a hobby.
- Consider the budget and time you are willing to allow for the project. Directly related to the initial factor, your budget is dictated by the purpose behind your aquaponics endeavor. For example, if you aim to grow plants commercially, you must spend some business capital worth of a budget. Regarding the time, aquaponics as a business venture would demand a large chunk of your day because you need to monitor everything to ensure a profitable harvest.
- Determine which aquaponics technique fits your situation. Of the three strategies discussed above, you should select one that suits your knowledge and community setting. Moreover, each method caters to specific types of plants.
- Decide what system you will adopt. Note that this refers to the scale of cultivation you aim to do. Small systems aquaponics would require you to employ lower nutrient concentrations. In this situation, you will have fewer fish resulting in less waste. Leafy green vegetables and herbs are compatible with small systems. On the other hand, large systems aquaponics entails higher concentrations of nutrients. Consequently, you would need more fish to produce more organic wastes.
What plants are best for deep water culture (dwc)?
Plants suitable for DWC should be lightweight and water-friendly. With this in mind, look at the shortlist of plants I have rounded up for deep water culture aquaponics.
Lettuce - This vegetable is one of the easiest plants to grow in any farming enterprise, including deep water culture. Lettuce is highly recommended because of its short growing cycle and notable market demand.
- pH range: 5.6 - 6.2
- Temperature: 45 – 70 ºF (7 - 21 ºC)
- Estimated harvest time: 5 to 6 weeks
Health benefits of lettuce:
- Lettuce is rich in vitamin K, which supports bone health.
- Lettuce can help in reducing weight because of its low-calorie content. A single serving of lettuce contains only five calories.
Kale - Kale is a perfect match for the DWC indoor growing method. This green is well-known for its flavor all across the world. It is used in a variety of international recipes due to its versatility and nutritional worth.
- pH range: 6.0 - 7.5
- Temperature: 45 – 85 ºF (7 - 29 ºC)
- Estimated harvest time: 9 to 11 weeks
Health benefits of kale:
- Kale is dense with many vitamins such as A, B, C, and K.
- Kale is rich in antioxidants that are recognized as heart-protective and anti-inflammatory.
Basil - Basil is a culinary herb with a distinctive scent. Each type of basil has its distinct smell, such as lemon basil, sweet basil, and cinnamon basil. Because of the optimum growing circumstances generated by warm water and sunlight, basil thrives in aquaponics systems.
- pH range: 6.2 - 6.8
- Temperature: 70 - 85 ºF (21 - 29 ºC)
- Estimated harvest time: 8 to 10 weeks
Health benefits of basil:
- Basil is traditionally used to treat snakebites and inflammation caused by colds.
- Basil contains eugenol and limonene; both are antioxidants that eliminate free radicals from the body.
What plants are best for nutrient film technique (NFT)?
From what we have learned about NFT, the plants that suit perfectly for this technique should have the following characteristics:
- Short harvest period
- The root system is minimal.
- Lightweight.
Spinach - This vegetable is an excellent diet as a source of good nutrition. Growing spinach in aquaponics via NFT provides you with pesticide-free and great-tasting organic spinach.
- pH range: 6.0 - 7.0
- Temperature: 45 – 75 ºF (7 - 24 ºC)
- Estimated harvest time: 6 weeks
Health benefits of spinach:
- One cup of spinach will give you vitamins A, C, calcium, and iron.
- It also contains antioxidants that help prevent cell damage.
Parsley - Parsley is a simple herb to grow compared to other vegetables because it is not a nutrient-demanding plant. Although it is commonly used as a garnish, the savory leaves are increasingly used in salads, seafood, potatoes, vegetables, soups, and omelets.
- pH range: 6.0 - 7.0
- Temperature: 45 – 75 ºF (7 - 24 ºC)
- Estimated harvest time: 5 to 6 weeks
Health benefits of parsley:
- Calories, carbohydrates, protein, fat, fiber, vitamin A, vitamin C, vitamin K, folate, and potassium are all found in parsley.
- Nutrients that protect the eyes are abundant in parsley.
Arugula - This easy-to-grow leafy green is one remarkable plant for aquaponics because it takes few nutrients to develop. Because arugula prefers chilly weather, it needs some cover throughout the summer months, as too much sun will make it bitter. Your aquaponics garden will benefit considerably from the addition of arugula.
- pH range: 6.0 - 7.0
- Temperature: 45 – 65 ºF (7 - 18 ºC)
- Estimated harvest time: 4 to 5 weeks
Health benefits of arugula:
- This tasty green is high in fiber and phytochemicals and is nutrient-dense.
- Sugar, calories, carbs, and fat are all low in arugula.
What plants are best for media-based aquaponics?
Numerous plants can be grown in a Media Bed aquaponics system, including those that do not thrive in other approaches. As long as the grow beds are the proper depth, it is possible to grow leafy greens, herbs, and fruiting crops simultaneously in media-based aquaponics.
Tomato - Tomatoes are a popular aquaponics crop, but because they require a lot of nutrients, they are best suited to larger, more established systems. They prefer a lot of sunlight and can grow to be between 2 and 6 feet tall. To ensure that they develop higher without interfering with one another, you'll need to build a support structure.
- pH range: 5.5 - 6.5
- Temperature: 75 - 85 ºF (24 - 29 ºC)
- Estimated harvest time: 8 weeks
Health benefits of tomato:
- It contains the antioxidant lycopene, which has been linked to reducing cancer and cardiovascular diseases.
- Tomatoes are also known to contain vitamin C, potassium, folate, and vitamin K.
Eggplant - Because eggplant has an extensive root system, it is best suited for media beds aquaponics. But you must consider the high nitrogen and potash requirements of this growth when designing your aquaponics setup.
- pH: 5.5 - 7
- Temperature: 70 - 80 ºF (21 - 27 ºC)
- Estimated harvest time: 8 weeks
Health benefits of eggplant:
- The plant is recognized to improve one's digestion.
- Eggplant could promote control of one's blood sugar.
Cucumbers - Cucumbers are ideal for aquaponics medium beds because of their prominent root structure. However, because of the size of their roots, they should not be planted near plumbing components, as the roots might clog pipes.
- pH: 5.5 - 6.5
- Temperature: 72 - 82 ºF (22 - 28 ºC)
- Estimated harvest time: 8 to 9 weeks
Health benefits of cucumbers:
- Cucumbers are an excellent diet for those who aim to reduce their weight.
- This vegetable aids in hydration because it is 96% water.
Carrots - Carrots are ideal for aquaponics medium beds because of their big root structure. However, because of the size of their roots, they should not be planted near plumbing components, as the roots might clog pipes.
- pH: 7.0
- Temperature: 59 - 64 ºF (15 - 18 ºC)
- Estimated harvest time: 4 to 8 weeks
Health benefits of carrots:
- The vegetable is rich in beta-carotene, which the body converts to vitamin A that improves human vision.
- The potassium in carrots helps control blood pressure.
What plants do not work well with aquaponics?
Despite the fact that aquaponics is an exceptional method of growing plants without soil, some plants do not go well with it.
Perennial plants such as trees are not recommended to grow using the aquaponics technique:
- They require a more extended period of growth before you can even harvest their fruits.
- These plants need an extensive supply of nutrients that means you should have more water and aquatic organisms.
- Their roots are complicated and become bigger over time. You would need immense growing beds to cater to their massive root system.
- Lastly, perennial plants that extend more than 4 feet tall threaten to destroy your aquaponics setup since they have this tendency to topple down.
Potatoes and sweet potatoes are also not recommended to grow in any aquaponics.
- These require soil to grow and mature.
- They have an extensive root system which makes it challenging for anyone to manage.
Corn also may be added to the list of plants not suited for the aquaponics approach.
- You would need enough headspace knowing that corn grows at an average of 8 feet high (2.5 meters).
- This plant has a very fibrous root system, it can clog your water pipes.
Aquaponics is an exciting and challenging approach to growing our favorite plants. You might just be seeking the best plants for aquaponic systems so you can experiment with growing your backyard vegetables. Remember, aquaponics provides the opportunity to grow significantly more plants and contribute to global food security whilst reducing your carbon footprint. I hope this article gave you enough information to choose which plant you will cultivate in your aquaponics setup.