7 Hardest Vegetables to Grow in Aquaponics and Why They Challenge Even the Experts
Growing vegetables in aquaponics is a sustainable and innovative way to cultivate food, but not all vegetables are easy to grow in this system.
Some crops require precise growing conditions that make them particularly challenging in aquaponics setups.
Below, we’ll dive into seven of the hardest vegetables to grow in aquaponics and the unique challenges they present.
1. Carrots
Challenges: Carrots are notoriously difficult in aquaponics due to their need for loose, well-drained soil, which is hard to replicate in standard grow beds.
Carrots need a medium like coconut coir or perlite for proper root development.
They also require consistent moisture without becoming waterlogged, which can be tricky to manage.
Additionally, overcrowding and poor aeration in the grow bed can result in misshapen roots.
Growing Tips:
Substrate: Use a fine, well-aerated grow media like coco coir or a mix of perlite and vermiculite.
Depth: Ensure at least 12 inches of growing depth for proper root development.
Climate: Ideal temperatures range from 13°C to 24°C or 55°F to 75°F.
Trellis or Stakes? No, but spacing is crucial.
2. Potatoes
Challenges: Potatoes are tuberous plants that require a deep growing medium for proper development.
This can be challenging in aquaponics, as grow beds are typically shallow.
Potatoes are also susceptible to waterlogging, which can cause root rot.
Managing humidity and airflow is crucial to prevent blight and fungal diseases, which spread easily in aquaponic environments.
Growing Tips:
Substrate: Use a loose, deep media like expanded clay or a special deep grow bed for better tuber development.
Climate: Potatoes grow best in cool, temperate climates with temperatures between 10°C to 24°C or 50°F and 75°F.
Trellis or Stakes? No, but a deep bed or mound is essential.
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3. Cauliflower
Challenges: Cauliflower needs careful temperature management and nutrient balance.
It requires cooler temperatures to avoid bolting and bitter heads.
A calcium deficiency can lead to issues like tip burn, which is hard to fix in a closed-loop aquaponics system ~ however if you are an experienced grower, this is often not an issue if you use calcium carbonate to buffer your pH
Cauliflower also demands consistent pH levels and precise control over humidity to prevent mould and rot.
They do need a lot of space to be able to grow, just like in the soil gardens, and very prone to pests.
Growing Tips:
Substrate: A well-draining medium like expanded clay pellets.
Climate: Maintain temperatures between 15°C to 21°C or 60°F and 70°F. Avoid hot, dry conditions that can cause bolting.
Trellis or Stakes? No, but space is critical for airflow.
4. Capsicums/ Bell Peppers
Challenges: Bell peppers have a long growing season and require high temperatures, steady light exposure, and nutrient stability.
They are particularly sensitive to fluctuations in water and nutrients, which can lead to stunted growth, blossom drop, or small, malformed fruits.
They also require protection from aphids and spider mites, which thrive in humid aquaponic environments.
For any fruiting plant, increased potassium is needed, which with experience can be added naturally or with the use of potassium carbonate to increase pH, which naturally drops during the nitrification process.
Growing Tips:
Substrate: A balanced mix of clay pellets and perlite for good drainage.
Climate: Optimal growing temperatures range from 21°C to 29°C or 70°F to 85°F. Keep a consistent light source.
Trellis or Stakes? Yes, use stakes to support plants as they grow tall and heavy with fruit.
5. Broccoli
Challenges: Broccoli demands cool temperatures and plenty of light, but it's prone to pests like cabbage worms, which can be difficult to manage in aquaponics.
It also needs adequate calcium and magnesium levels to prevent issues like poor head formation and stunted growth. Keeping a steady pH and nutrient balance in the water is essential.
Growing Tips:
Substrate: A loose, well-draining grow media like hydroton.
Climate: Broccoli thrives in cooler temperatures between 55°F and 65°F (13°C to 18°C).
Trellis or Stakes? No, but adequate spacing is important to avoid overcrowding.
I grew 4 of these sized broccoli this year in a small, courtyard aquaponics system easily ~ powered by goldfish.
Don't forget, you can eat the leaves and stalks of the broccoli plant too!
When you are beginning, everything is daunting, but after a while, everything gets easier.
Learn More About Aquaponics
Check out the COURSES page to learn how you can get started with aquaponics now. Click HERE.
6. Garlic
Challenges: Garlic requires a period of cold (vernalization) to trigger bulb formation, which is difficult to manage in the controlled environment of an aquaponics system.
Additionally, garlic has a long growing season, often up to six months, which is longer than most aquaponic crops. It also needs well-drained soil, which can be tricky to achieve in typical grow beds.
Growing Tips:
Substrate: Use perlite or coarse sand mixed with hydroton/ expanded clay for better drainage.
Climate: Cool temperatures 0°C to 10°C or 32°F to 50°F or for vernalisation, followed by moderate temperatures 10°C to 21°C or 50°F to 70°F.
Trellis or Stakes? No, garlic grows underground and doesn’t need support.
7. Eggplant
Challenges: Eggplants thrive in high temperatures but are very sensitive to humidity and nutrient fluctuations.
They need consistent watering and a stable nutrient supply to prevent blossom end rot.
They are also vulnerable to pests like spider mites and aphids, which can wreak havoc in humid aquaponic systems.
Growing Tips:
Substrate: Use a well-draining medium like expanded clay pellets.
Climate: Keep temperatures between 24°C to 29°C or 75°F and 85°F for optimal growth.
Trellis or Stakes? Yes, eggplants benefit from stakes or cages to support the weight of the fruit.
Check this video out....
Why These Vegetables Are Challenging in Aquaponics
The common difficulty with these vegetables is their specific needs for nutrients, climate control, and growing conditions.
Aquaponics, while versatile, can struggle to meet the particular requirements of root vegetables or crops with longer growing seasons, fluctuating water needs, or a sensitivity to temperature and humidity changes.
It is completely possible, but just at the more advanced level of growing in aquaponics
Check out My YouTube Channel 'Candy The Aquaponics Lady'
Aquaponics is an ecosystem, and with anything it takes time to learn how it works. So, sit back and binge watch my 'how to' playlist and the 'Water Quality Made Simple' Playlist, and learn the next steps in your aquaponics system as you create the ecosystem.
Here are the next 2 videos I recommend you watching to create your ecosystem ~ before you add any fish
How Aquaponics Works as an Ecosystem
How to Cycle Your Aquaponics System (How to colonise it with bacteria)
Learn More About Aquaponics
Check out the COURSES page to learn how you can get started with aquaponics now. Click HERE.
Want to get your Eyes and Hands on the FREE Online Aquaponics Essentials Course?
This is a great free resource to really understand how aquaponics is a sustainable ecosystem that will grow your organic food is a productive way.
You learn how all the 'parts' make up the 'whole', and helps to give you the foundations of understanding aquaponics.
Sign up HERE
Want to help out and Feed my Fish?? (They don't drink coffee)
Candy Alexander is a dedicated aquaponics enthusiast with a wealth of formal training in aquaculture. Over the past 15 years, Candy has been deeply immersed in both commercial and backyard aquaponics, honing her skills and expertise in this sustainable farming method.
Candy's passion lies in making aquaponics accessible to everyone. With a mission to simplify aquaponics, she believes that anyone can embark on this sustainable journey.
She encourages those new to aquaponics to "kick the tires" without a significant financial investment. Her guidance focuses on helping people start their aquaponics journey with small-scale systems, ensuring a low barrier to entry for newcomers.
Candy shares practical tips, step-by-step guides, and personal stories to inspire and guide readers on their aquaponics adventure. Whether you're a seasoned farmer or a curious beginner, Candy Alexander is your go-to source for simplifying aquaponics and fostering a sustainable gardening experience.