Aquaponic is a balanced and self-sustainable way for raising fish (aquaculture) and growing plants without soil (hydroponics).
It has been done on a small-scale for years by hobbyist farmers and continues to expand and become commercialized due to food demand and technology.
It involved three organisms that benefit one another:
- The fish feed the plants by their nitrogenous waste
- The plants clean the water for the fish to be healthy
- The beneficial bacteria convert the ammonia from fish waste to nitrites, then nitrates, which become nutrients accessible to plants.
At the same time, the fish are living in ammonia-free conditions, and fish create ammonia, which is toxic to them. Are you interested yet in entering the growing community of global aquaponics farmers?
What You Can Expect to Learn: This article is to help you, whether for fun, to get some extra fresh vegetables in your backyard, or make some dollars with the crop, in selecting the best plants in aquaponics for the small-scale system.
Factors to Consider When Choosing the Best Plants for Small Scale Aquaponics
There is a long list of plants that do well in an aquaponics system, but the nutrient requirements for the plant and susceptibility to other conditions will separate which plant does well in small systems, or not.
When selecting the best plants for a small scale aquaponics, keep the following factors in mind.
The Aquaponics Design
Different designs require different types of plants.
One plant may grow exceptionally well in a nutrient film technique (NFT) system and not at all in a media bed.
Some plants may not grow well in a deep water culture system, yet flourish in a grow tower.
In all cases of planning your garden you need to select the plants that are compatible with your design system.
Nutrient Demand
The demand for nutrients in aquaponics will vary among different plants.
Some plants are more “nutrient-hungry” than other plants and will experience nutrient deficiency if there are not enough.
There are also plants that require less than what you might have available, and over-supplied nutrients will overload the system with more waste for the water, which can increase stress levels in fish.
Decision Making: Keep in mind that you have a specific number of fish, and you will have to determine how many of that particular type of plant the amount of fish is able to sustain in a balanced and seamless manner.
Environmental Conditions
Plants need different forms of optimum conditions for to grow.
These conditions relate to the pH, temperature of the water, sunlight, and temperature of the surrounding air.
Choose plants that are recommended for the pH of your system.
For example, peppers naturally need several hours of sunlight and will only do well if your aquaponics is outdoors.
Your Space
Certain plants grow quickly and reproduce quickly.
While others such as the strawberry require a large amount of space to produce a sufficient harvest.
Make sure that when you choose the plant to grow you are viewing it in relation to the space you have available.
Your Preference
The garden should be fun, and you should even be growing a plant that you enjoy growing, not just any plant that can fit in the system.
Growing a plant that you enjoy, similar to a job that you enjoy, will make things seem like a hobby and you won’t get burned out or bored of taking care of the plants!
You Call it: If you are a herb person, choose ginger, parsley, mint, etc. If you enjoy colourful gardens, choose flowers like pansies, roses, or marigolds.
10 Best Plants for Small Scale Aquaponics
Small vegetables and flowers that don’t require elevated nutrient levels make an ideal plant for small-scale aquaponics.
The 10 best plants for small to medium sustainable aquaponics are:
- Kale
- Spinach
- Watercress
- Basil
- Lettuce
- Parsley
- Arugula
- Swiss chard
- Rosemary
- Bok Choy
Kale
Kale is an everyday vegetable that is considered a household treat.
It requires low nutrient levels and has a successful pH range of 6-7.5.
In addition, kale does not have strict water temperature parameters because it can be successful when temperatures are in the range of 55 to 75 degrees Fahrenheit.
After five to six weeks after planting, you can start harvesting healthy and leafy kale to add to your dish or sell at your local market.
Spinach
Spinach is a particularly popular, low-nutrient plant to grow in a small aquaponics system and is one of the most widely consumed vegetables in homes across the globe.
This leafy vegetable prefers a pH range of 6.0 to 7.0, while the ideal water temperatures for production are between 45 and 75 degrees Fahrenheit.
As a recommendation, spinach is especially ideal for NFT aquaponics, as it has short and thin roots and will not clog the pipes.
Watercress
Watercress is a fast growing and easily produced crop.
It is a good crop for new aquaponics operators for small scale aquaponics.
You can grow watercress with other leafy vegetables as long as you monitor the growth and they do not outgrow the slower growing vegetables.
Watercress will grow adequately at pH levels between 6.5 to 7.5 and at a temperature between 50 and 60 degrees Fahrenheit.
Basil
If you’re considering a fast-growing, water-loving leafy vegetable for a small-scale aquaponics project, basil would be a great option.
It will germinate within a week and you’ll be able to harvest within 3 – 4 weeks!
But remember, basil grows well in warm temperatures so you need to maintain a temperature of 65 – 85 Fahrenheit.
For pH, basil prefers k slightly acidic pH range of 5.5 – 6.5.
Lettuce
Lettuce is a green leafy vegetable that can be grown with lower nutrient levels.
For small-scale farmers, it is one of the best plant options for aquaponics systems, especially because it can grow with different changes in growing conditions.
The plant grows best within an air temperature range of from 60 to 70 F and a pH level of 5.5 to 6.5.
Parsley
Parsley is a well-loved herb and a part of many home recipes.
It does not require low nutrients to grow and makes it good for new and small scale aquaponics farmer.
The optimal temperature spectrum for growing parsley is between 60 and 80 degrees Fahrenheit which it prefers in warm conditions.
Parsley grows perfectly in almost neutral conditions of between 6 and 7 pH.
Arugula
This plant is most suited for cooler conditions, where temperatures oscillate between 45 and 65 degrees Fahrenheit.
It is leafy, green, and resilient to disease and pests.
If you want to grow Arugula in the summer months, give the direct sun some cover, but allow it to get several hours of sunlight a day.
Arugula grows best in almost neutral soil conditions between 6.0 and 7.0.
Swiss Chard
Swiss chard is a great plant for beginners, with a growing time of four to five weeks.
Swiss chard will thrive in slightly acidic to neutral pH, so it is a good choice for aquaponics.
Swiss chard is also a good winter plant because it is frost tolerant.
However; the best growing conditions are between 60 and 75 degree Fahrenheit.
Rosemary
Rosemary is a commonly used herb, and can be grown in an aquaponics system.
The herb grows well in the water, has limited pest problems, uses very low levels of nutrients, and makes a terrific plant for small aquaponic systems.
Rosemary generally does best in broadly-neutral pH conditions ranging from 6.0 to 7.0.
The best temperature to grow Rosemary is approximately 70 degrees Fahrenheit.
Bok Choy
This type of Chinese vegetable, has become one of the most popular varieties of all vegetables, mainly due to its nutritional and beneficial health properties.
It is well suited to a small scale deep water culture aquaponics system. It requires low amounts of nutrients, so we can obtain a good result with a low number of fish.
Bok Choy does well within a slightly acidic to neutral balance, in the 6.0 to 7.5 ranges.
This plant needs to be in cold temperatures around 30 degrees Fahrenheit.
Wrap Up
Aquaponics is a great self-sustaining system because it allows you to raise fish and grow plants simultaneously.
However, with different sizes of aquaponics comes different types of the plants needed. Small-scale aquaponics have lower amounts of nutrients than large-scale aquaponics.
That is why you must choose low nutrient plants.
Some examples include small leafy vegetables including kale, spinach, watercress, basil, bok choy, and lettuce.