The Best Flowers for Aquaponics Systems

While many aquaponics systems focus on growing edible plants like herbs and vegetables, flowers can also be an excellent addition. Not only do they add beauty and fragrance to your setup, but they can also attract beneficial pollinators, support system biodiversity, and even help with pest management.

Choosing the right flowers for an aquaponics system is essential to ensuring they thrive in a water-based environment. In this blog, we will explore the best flower options for aquaponics, factors to consider when growing them, and tips for successfully integrating flowers into your system. Whether you’re looking to enhance your garden’s aesthetics or reap the benefits of companion planting, these flowers are sure to make your aquaponics system bloom in more ways than one!

Factors to Consider When Growing Flowers in Aquaponics

Below are the key factors to consider when growing flowers in your aquaponics system.

1. Water Requirements and Tolerance

Aquaponics is a water-based system, meaning that plants must be able to adapt to constant access to water. Some flowers are naturally suited to wetter environments, while others may struggle if their roots are too waterlogged. So it’s essential to select flowers that can handle a high level of moisture or that thrive in aquatic conditions.

For example, flowers like water lilies are naturally adapted to water and thrive in aquatic environments, making them an ideal choice for aquaponics. On the other hand, plants with low tolerance for moisture, such as those prone to root rot, may not do well. Always check the specific water tolerance of the flower species you are considering to ensure compatibility with your setup.

2. Nutrient Absorption and Compatibility with Fish Waste

Flowers grown in an aquaponics system need to be able to absorb nutrients in a similar way to vegetables and herbs. Some flowers are heavy feeders and may require more nutrients, while others are more conservative in their uptake.

It's important to match flowers with nutrient needs that align with the fish population and the overall nutrient availability in your system. Flowers like marigolds and nasturtiums can easily absorb the nitrates from fish waste and are relatively low-maintenance. On the other hand, nutrient-hungry flowers might compete with vegetables for resources, so careful planning is needed to avoid nutrient imbalances.

3. Light Requirements

Like any other plant, flowers require adequate light to photosynthesize and thrive. The amount of light needed can vary significantly between different species of flowers. Some prefer full sunlight for most of the day, while others can tolerate or even thrive in partial shade. When integrating flowers into your aquaponics system, it’s important to provide enough light, either from natural sunlight or grow lights, to meet the needs of your chosen species.

Consider how your lighting setup aligns with the flowers you plan to grow. For instance, sun-loving flowers like lavender will require plenty of light, while others, like calendula, can tolerate some shade. If your aquaponics system is indoors, the artificial grow lights should mimic the natural light cycle needed for optimal flower growth.

4. Temperature and Climate Considerations

Temperature plays a crucial role in both the health of your fish and the plants in your aquaponics system. Most flowers have specific temperature ranges they prefer, so it’s essential to choose flowers that can thrive in the same temperature range that is comfortable for the fish species you’re raising.

Warmwater fish, like tilapia, may be paired with flowers that thrive in warmer climates, such as marigolds or nasturtiums. If you are raising cold-water fish, like trout, you may need to select flowers that can handle cooler temperatures. You should also consider the possibility of temperature fluctuations, especially if your system is outdoors, and choose resilient flowers that can cope with varying environmental conditions.

5. Space and System Size

The size of your system will determine the number and types of flowers you can grow. Some flowers have extensive root systems or grow tall and bushy, requiring more space to thrive, while others are more compact and can be integrated into smaller systems.

For smaller or vertically stacked aquaponics systems, compact flowers like nasturtiums or marigolds are ideal, as they won’t overwhelm the space or block light for other plants. For larger systems, you can opt for larger, more robust flowers that have ample room to spread. Additionally, consider how the growth of the flowers will impact the airflow, light access, and maintenance requirements of your system. Make sure the flowers don't overcrowd other plants or interfere with system components like grow beds and water circulation.

The Best Flower Choices for Aquaponics Systems

When choosing flowers for your aquaponics system, it’s important to select varieties that can thrive in the water-based environment and complement the overall health of the system. The following flowers have proven to be excellent choices for aquaponics due to their adaptability, benefits to the ecosystem, and aesthetic value.

1. Nasturtium

Nasturtiums are attractive, vining flowers with circular leaves and vibrant blooms that range from yellow to orange and red. They are known for their trailing growth habit, making them perfect for hanging baskets or cascading down the sides of grow beds.

Edible Flowers and Leaves:

• Edible Value: Both the flowers and leaves of nasturtiums are edible, with a peppery flavor similar to arugula. They can be used in salads, garnishes, or as herbal infusions, adding an edible, functional element to your aquaponics garden.

• Attract Beneficial Insects: Nasturtiums attract pollinators like bees and butterflies, which can boost the productivity of fruiting plants in the system.

Low-Maintenance Option for Beginners:

Nasturtiums are easy to grow in aquaponics due to their low nutrient needs and adaptability to moist environments. They are also fast-growing, providing quick results for new growers looking to add color and edible flowers to their system.

2. Marigolds

Marigolds are hardy, brightly colored flowers known for their rich orange, yellow, and red blooms. They are annuals that are easy to grow and can adapt well to a variety of conditions, making them a popular choice for aquaponics systems.

Benefits in Aquaponics:

• Pest Deterrent: Marigolds are famous for their ability to repel certain pests, especially nematodes, whiteflies, and aphids. Their natural compounds, such as thiophene, act as insect repellents, which helps protect other plants in the aquaponics system.

• Ease of Growth: Marigolds are resilient and low-maintenance,they can tolerate the moisture levels present in most systems and don’t require high levels of nutrients to thrive.

• Biodiversity: Adding marigolds enhances the biodiversity of your system, creating a more balanced ecosystem.

3. Lavender

Lavender is a perennial herb known for its aromatic purple flowers and silvery-green foliage. It is prized for its soothing fragrance and ornamental beauty.

Aromatic Benefits and Insect Repellent Properties:

• Aroma: Lavender’s strong scent has a calming effect, making it an excellent choice for creating a tranquil aquaponics environment. It adds a pleasant fragrance that enhances the overall sensory experience of the garden.

• Natural Insect Repellent: Lavender’s essential oils repel unwanted insects like mosquitoes and moths. 

• Moderate Water Tolerance: While lavender prefers drier soil in traditional gardens, it can still thrive in an aquaponics system when its roots are well-aerated.

4. Calendula (Pot Marigold)

Commonly referred to as Pot Marigold, calendula is a bright, daisy-like flower with golden yellow to orange blooms. It is an annual flower that is often grown for both its beauty and medicinal uses.

Medicinal Uses and Compatibility with Aquaponics:

• Healing Properties: Calendula flowers are widely used in natural remedies for their anti-inflammatory, antibacterial, and antifungal properties. They are often used in teas, salves, and oils for healing wounds and soothing skin irritations.

• Easy to Grow in Aquaponics: Calendula thrives in aquaponic systems due to its tolerance for moist conditions and ability to absorb nutrients from fish waste efficiently. It also acts as a companion plant, improving the overall health of the system by repelling harmful pests like aphids.

5. Orchids (for Advanced Systems)

Orchids are exotic flowering plants known for their intricate, colorful blooms and long-lasting flowers. They come in a variety of species, each with unique care requirements. While orchids are often seen as challenging to grow, they can be successfully integrated into aquaponics systems with the right conditions.

Considerations for Aquaponic Orchid Care

• Advanced Care Requirements: Orchids need specific conditions to thrive, including well-regulated humidity, consistent temperatures, and proper airflow. They are best suited for advanced aquaponic growers who can maintain these environmental parameters.
• Air Roots and Water: Orchids typically grow with their roots exposed to air, so aquaponics systems that use media beds or systems with misting components are ideal for their growth. They should not be submerged in water but rather kept in a system where their roots can absorb moisture and nutrients without being waterlogged.
• Aesthetic Appeal: Orchids are highly ornamental and can add a touch of elegance and sophistication to your aquaponics system. Their stunning blooms are a reward for experienced growers willing to provide the attention they require.

6. Water Lilies

Water lilies are aquatic plants with large, flat floating leaves and stunning, fragrant flowers that bloom in a variety of colors, including white, pink, yellow, and red. They are one of the most iconic water plants, known for their beauty and elegance.

Ideal for Water-Based Systems, Aesthetic Value:

• Adaptation to Aquaponics: Water lilies are perfectly suited to aquaponics systems with deep water components or ponds. They thrive in water and require little maintenance, making them an ideal aesthetic addition to the setup.

• Aesthetic and Habitat Benefits: Their large, floating leaves create shaded areas in the water, which can help reduce algae growth and provide shelter for fish. The flowers themselves add a striking visual element, enhancing the beauty of the aquaponics system.

• Promotes Oxygenation: Water lilies also aid in oxygenating the water, improving the overall health of both plants and fish.

Tips for Integrating Flowers into Your Aquaponics System

Incorporating flowers into your aquaponics system can enhance both the visual appeal and functionality of your garden. However, ensuring that the flowers coexist harmoniously with other plants and fish in the system requires some planning and care. Here are essential tips for successfully integrating flowers into your aquaponics system.

1. Balancing Flowers with Other Plants 

When adding flowers to your aquaponics system, it’s important to maintain a balance with the other plants, such as herbs and vegetables. Flowers should not overshadow or outcompete the crops you’re growing for food. Achieving balance involves:

• Choosing Complementary Species: Select flowers that have similar nutrient and light requirements as the other plants in your system. For example, flowers with moderate nutrient needs like nasturtiums or marigolds work well alongside herbs like basil or leafy greens. Avoid pairing heavy feeders with nutrient-light plants to prevent one from starving the other.
• Companion Planting: Many flowers can benefit herbs and vegetables by acting as companion plants. For example, marigolds can help deter pests that might otherwise damage crops like tomatoes or peppers. Nasturtiums, with their trailing growth habit, can be planted at the edges of grow beds, leaving room for vegetables to thrive in the center.
• Spacing and Growth Habits: Consider the growth habits of your flowers. Some flowers, like nasturtiums, have a sprawling growth habit that can be used to fill spaces between vegetable plants. Taller flowers like sunflowers or lavender should be placed where they won’t block light from other plants or compete for root space.
• Managing Competition for Resources: Flowers and food crops share the same nutrient pool in aquaponics systems. Monitor how the addition of flowers impacts the nutrient levels for other plants. If flowers begin to compete with crops for nutrients, you may need to adjust your fish feeding regime, increase stocking density, or add supplements like iron or potassium.

2. Monitoring Water pH and Nutrient Levels

Flowers, like any other plant, will draw nutrients from the water, which can affect the overall balance of your system. Some key considerations include:

• pH Levels: Many flowers thrive in slightly acidic to neutral water (pH 6.0-7.0). However, the pH must also be suitable for your fish and other plants. Regularly monitor your water pH to ensure it stays within the optimal range. If it starts to drift, you may need to adjust it using natural pH buffers like calcium carbonate or potassium bicarbonate.
• Nutrient Balance: If too many flowers are added or if they are heavy feeders, it could deplete nutrient levels, causing deficiencies in other plants. Monitor nutrient levels regularly using test kits to ensure adequate nutrition for all plants in the system. If deficiencies occur, you can either increase fish feeding or add supplemental nutrients that won’t harm the fish.
• Water Temperature: Flowers have different tolerance levels for temperature. Make sure the temperature of your water matches the ideal range for both your flowers and your fish.

3. Regular Pruning and Maintenance

Like any plant, flowers in aquaponics systems require regular maintenance to stay healthy and avoid becoming a burden on the system. Proper pruning, deadheading, and routine care are essential to ensure flowers don’t overgrow and outcompete other plants for light and nutrients.

• Pruning: Regularly prune flowers to encourage new growth and maintain a manageable size. Pruning helps flowers stay within their allocated space, allowing more light and air circulation for nearby plants. It also helps prevent overcrowding, which can lead to fungal diseases and nutrient competition.
• Deadheading: Removing spent or dead flowers, known as deadheading, can encourage continuous blooming and prevent energy from being diverted into seed production. This practice helps maintain the aesthetic value of the flowers and keeps them healthy, ensuring they don’t waste resources.
• Disease and Pest Control: Although some flowers, like marigolds and lavender, naturally deter pests, others may attract insects or develop fungal diseases. Inspect your flowers regularly for signs of infestations or disease. If you spot any issues, address them quickly using natural pest control methods, such as introducing beneficial insects (like ladybugs) or applying safe, fish-friendly organic treatments.
• Managing Growth Patterns: Some flowers, like nasturtiums, can become quite sprawling. Use trellises or other support structures to manage their growth and keep them from overtaking the system. This will ensure that your flowers coexist peacefully with other plants and don't block light or overcrowd the space.

4. Avoiding Toxic Flowers That Could Harm Fish

While many flowers are safe and beneficial in aquaponics, some can be toxic to fish and should be avoided. Certain flowers contain compounds that, when leached into the water, can negatively affect the fish’s health or even lead to fatalities. To prevent issues:

• Research Before Planting: Always research any flower you’re considering for your aquaponics system. 
• Stick to Safe, Tested Flowers: Stick to flowers that are known to be safe for fish and compatible with aquaponics environments, such as marigolds, nasturtiums, lavender, and calendula. 
• Consider Organic, Non-Treated Seeds: When choosing flowers for your aquaponics system, always opt for organic, non-treated seeds or seedlings. Flowers treated with pesticides or chemicals can introduce toxins into the water that harm both fish and plants.
• Monitor Fish Behavior: After introducing new flowers to the system, closely observe the behavior of your fish. If you notice signs of stress, unusual behavior, or illness, it may be due to the introduction of a toxic flower or chemical contaminant.

Common Challenges in Growing Flowers in Aquaponics and How to Overcome Them

Integrating flowers into an aquaponics system can bring numerous benefits, but it also presents unique challenges. Below are common challenges you may encounter and strategies to overcome them.

1. Algae Growth and Water Quality Issues

Algae can thrive in aquaponics systems, especially when light and nutrients are abundant. Excess algae growth can clog pipes, pumps, and filters, reducing water circulation and oxygen levels. Algae can also compete with plants (including flowers) for nutrients, leading to stunted growth or  nutrient deficiencies. Furthermore, algae blooms can lower water quality, affecting fish health and the overall stability of the system.

How to Overcome It:

• Minimize Light Exposure to Water: Algae need light to grow, so reducing the amount of light that hits the water surface can significantly limit its growth. Use floating plants like water lilies to create shade or cover open areas of water with shading materials to block direct sunlight. Additionally, ensure that grow beds are covered properly, preventing light from reaching the water beneath.
• Control Nutrient Levels: Algae feed on excess nutrients in the water, particularly nitrogen and phosphorus. To prevent this, avoid overfeeding your fish, as excess food can break down into nutrients that promote algae growth. Make sure the fish stocking density is balanced so that plants and flowers can absorb nutrients efficiently, leaving less for algae.
• Improve Water Circulation: Ensure that your system has adequate water flow and aeration. Proper water circulation keeps oxygen levels high, which inhibits algae growth and helps plants and fish thrive. Use air stones or pumps to increase oxygenation, especially in areas where algae are likely to accumulate.

2. Pests and Diseases

Some flowers may attract unwanted insects, and fungal diseases can spread in the humid environment. These  pests and pathogens can affect both the flowers and the other plants in your system, potentially reducing yields or damaging the entire setup.

How to Overcome It:

• Use Natural Pest Deterrents: Select flowers that naturally deter pests, such as marigolds, nasturtiums, and lavender. Companion planting with pest-repelling flowers can help protect more vulnerable crops.
• Introduce Beneficial Insects: Insects like ladybugs, lacewings, and predatory mites can naturally control pest populations without the need for chemical pesticides. These beneficial insects feed on harmful pests such as aphids and mites, keeping infestations in check while maintaining a balanced ecosystem.
• Organic, Fish-Safe Treatments: If you need to intervene to control pests, use organic, fish-safe treatments like neem oil or insecticidal soap. Apply these treatments carefully, and ensure that they do not contaminate the water and harm the fish. 

• Monitor Humidity and Airflow: High humidity in an aquaponics system can lead to fungal diseases like powdery mildew or root rot, especially for flowers that require good airflow, such as lavender or calendula. Ensure proper ventilation in your growing area by using fans or adjusting the layout to improve air circulation. Prune flowers regularly to prevent overcrowding and promote airflow between plants.

3. Adjusting Fish Stocking Density for Optimal Nutrient Balance

Maintaining the right fish stocking density is crucial for the nutrient balance in your aquaponics system. Too few fish may not produce enough nutrients for the plants and flowers, while too many fish can lead to an excess of waste, which could overload the system and harm both plants and fish. An imbalance in fish stocking density can result in poor plant growth, water quality issues, and stress on the fish.

How to Overcome It:

• Start with Balanced Stocking: Begin with a stocking density that matches the size of your system and the nutrient needs of your plants and flowers. A general rule of thumb for aquaponics is to stock about 20-25 kg (44-55 lbs) of fish per 1,000 liters (264 gallons) of water. However, this can vary depending on the type of fish, the number of plants, and the nutrient demands of your system.
• Monitor Nutrient Levels: Use regular water testing to monitor key parameters like ammonia, nitrate, and nitrite levels. These will give you an indication of whether the nutrient levels are too high or too low.
• Increase Plants to Absorb Excess Nutrients: If you notice an excess of nutrients, consider adding more plants or flowers to absorb them. Flowers like marigolds and nasturtiums can help stabilize nutrient levels by absorbing nitrogen efficiently. You can also add fast-growing plants like lettuce or spinach to quickly use up excess nutrients and maintain system balance.
• Fish Feeding and Growth Stages: Adjust your fish feeding practices based on their growth stages. Growing fish tend to consume more food and produce more waste, so you may need to monitor the system closely during these stages to avoid nutrient overload. 
• Supplemental Nutrients for Flowers: If you have a low fish stocking density and the nutrient levels are insufficient for flowers and other plants, you can add fish-safe supplemental nutrients like iron or potassium. 

Conclusion

Growing flowers in an aquaponics system offers a unique way to combine beauty with functionality. From vibrant marigolds that deter pests to fragrant lavender that repels insects and enhances your environment, flowers can elevate your system’s aesthetic appeal while promoting biodiversity and ecosystem health. By selecting the right flowers, balancing nutrient levels, and managing water quality, you can enjoy the rewards of a thriving, sustainable garden.

Now it’s time to take the next step! Experiment with some of the recommended flowers and watch your aquaponics system flourish. Share your results, tips, and favorite flower combinations with other growers in the community. Ready to grow? Start by choosing your first flower variety today and bring more color and life to your aquaponics garden!