Basil is one of the most popular plants to grow in aquaponics. It’s easy, fast, and hardy, making it a great choice for first-time growers, hobbyists, and commercial growers alike. Additionally, as basil is a high-demand herb, it’s easy to market and sell to just about anyone.
Here’s everything you need to know about growing basil in aquaponics.
Growing Conditions
- pH: 5.5 to 6.5
- Temperature Range: 64 to 86 F (18 to 30 C)
- Ideal Temperature: 68 to 77 F (20 to 25 C)
- Germination: Takes 6 to 7 days under optimal conditions
- Light Exposure: Sunny and/or slightly shaded
- Harvest Time: 5 to 6 weeks or when plant is around 15 cm tall
- Plant Height Maturity: 30 to 70 cm
- Plant Width Maturity: 30 cm
- Recommended Aquaponic System: NFT, DWC, Media Beds
How to Grow Basil in Aquaponics
Like other plants grown in aquaponics, the process consists of three phases: Germination, Transplanting, and General Maintenance/Care.
1. Germination
To start the germination process, establish a small grow bed and place your seeds 1/2 cm deep into a growing medium (such as coco coir, a grow sponge, or rockwool). Pump water into your grow bed for about a half-hour each day with temperatures (air) between 68 to 77 F (20 to 25 C).
Under these conditions, your basil should take approximately 6 to 7 days to germinate.
2. Transplant Seedlings
Once your basil has at least 4 to 5 true leaves, transplant your seedlings into your aquaponic unit. And although you could probably get away with transplanting after 2 leaves, in aquaponics, you want the seedlings to be a little more established. Because you’re not using soil, larger seedlings with larger roots will have a higher success rate when trying to re-anchor themselves.
2. Basil Maintenance and Care
Once transplanted, your basil will need fairly warm temperatures — 64 to 86 F — to grow properly. And because basil actually enjoys the heat, you shouldn’t have a problem growing it directly under the sun. However, here at Ponics Life, we recommend that you provide a little bit of shade as this will improve the quality of the leaves.
Additionally, if you’re growing in temperatures above 80 F (27 C), then make sure you’re ventilating or using a 20 or 30 percent shading net to prevent tip burn.
3. Fish Maintenance and Care
Because you’re growing basil aquaponically and not hydroponically, you also need to think about your fish. Whatever fish you’re using, remember to monitor and care for them just like you would your plants. If you can’t keep your fish alive, your plants aren’t going to grow.
And while we won’t go into the details here, we recommend you read our “Best Fish for Aquaponics” guide and our “Fish Health and Disease” guide to learn more.
Harvesting Aquaponic Basil
Harvesting basil in aquaponics is very easy and follows the same basic steps as soil-grown basil.
1. Cut and Remove
When your plants reach about 15 cm in height, you can start harvesting the leaves. To do this, all you need to do is cut about 1/4 inch above a node. Once cut, simply remove the leaves and move on to the next plant. As basil actually enjoys pruning, you should be able to harvest leaves for about 30 to 50 days following your first harvest.
2. Remove Flowering Tips
If you want to avoid a bitter taste to your basil, then you need to remove the flowering tips that emerge from the top-center of the plant. Because the flowers take energy and nutrients away from the leaves, getting rid of them will encourage branching and make the remaining leaves more flavorful.
What Aquaponic System Should You Use for Basil?
There are three systems that are suitable for aquaponic basil: NFT, DWC, and Media Beds. And while there are pros and cons to each one, choose one that makes the most sense for your specific growing needs.
If you want to do a deep dive on each system, make sure to check out our “Types of Aquaponic Systems” Guide.
Media Beds for Basil Aquaponics
- Simple, popular design that will grow basil quickly
- Easy for beginners (which pairs well with basil)
- Better for small setups as large media bed setups can get expensive
Nutrient Film Technique (NFT) for Basil Aquaponics
- Basil does really well in commercial NFT systems
- Way more complicated than Media Beds
- Provides the ability to farm vertically and stack rows of basil
Deep Water Culture (DWC) for Basil Aquaponics
- Basil does really well in commercial DWC systems
- May be difficult to master for the beginner
- Is more complicated than Media Bed Aquaponics
Benefits of Aquaponic Basil
There are a lot of benefits to growing basil in aquaponic systems, but there are two that really stand out: (1) basil is extremely hardy and forgiving, and (2) basil grows pretty fast in aquaponics.
Basil is Hardy and Forgiving!
Basil is a great starter plant simply because it’s hardy and forgiving. So regardless of your personal growing experience, you should be able to grow it fairly easily even in suboptimal conditions. Some growers have even had success growing it without fish or added-in nutrients and just using water.
Growing Basil is Fast!
The other great thing about basil is that it grows fast (at least comparatively). If given the right conditions, you should be able to harvest basil in a little over a month. Or, if you’re ok with smaller leaves, then you probably don’t have to wait a month. Ultimately, the timing and growth rate really depends on your system, preference, and growing ability.
Outdoor vs Indoor Considerations
When considering outdoor vs indoor aquaponics for basil, you have three options: (1) in your backyard exposed to natural light, (2) in a greenhouse with indirect light, or (3) completely indoors with artificial light. Your choice really depends on what’s available to you.
1. Backyard for Basil
If you plan on growing basil outside in the elements, remember to think about basil’s specific growing needs (discussed above). If your environment isn’t suitable for basil and the conditions aren’t right, then more likely than not, you’re basil is going to have a hard time (even if it is considered one of the hardier plants). Or, if conditions are out of the optimal range completely, then it’s not going to grow at all.
Things to Consider:
- Can’t regulate environmental conditions (temperature, storms, sunlight, etc.)
- May have to use a shade net if temperatures go over 80 F (27 C)
- Evaporation rates will be higher in your fish tank
2. Greenhouse for Basil
If you’re using a greenhouse for your aquaponics setup, then your basil should do just fine under the right conditions (good ventilation, temperature, etc.). As a greenhouse offers protection from outside influences (like pests), then your fish and plants should do really well together.
Things to Consider:
- A greenhouse can be expensive
- A greenhouse requires space
- You can regulate some conditions but not all
3. Indoor for Basil
Growing indoors is the best way to give your basil exactly what it wants and needs to grow year-round. If given the right artificial conditions, your plants will receive the perfect amount of light, air, and temperature, making it the best option of the three.
However, depending on how much space you have available, this can be hard to do if you’re an aquaponic hobbyist. So unless you already have a freshwater aquarium set up and ready to go (or space for one), it’s probably best to avoid this option as a beginner. Try growing outside first, then expand indoors when the option presents itself.
Things to Consider:
- Requires a lot of indoor space
- Handling and managing water inside can be difficult and risky
- If you’re a hobbyist, then you’re probably limited to aquarium/ornamental fish due to space requirements
Types of Basil
According to the Food and Agricultural Organization of the United Nations (FAO), any type of basil will do well in aquaponics. However, out of the more than 150 species of basil in existence, there are three types that have been proven to flourish in aquaponic systems across the world: Sweet Basil, Lemon Basil, and Purple Passion Basil.
1. Sweet Basil (Italian Genovese Basil)
Sweet basil is one of the most popular basil types. As an aromatic herb, sweet basil has a distinctive sweet and spicy taste to it that’s distinguishable from other varieties. Commonly used in Italian dishes, sweet basil grows 12 to 18 inches tall with both small leaves and lettuce-sized leaves achievable.
2. Lemon Basil
Lemon basil is a common herb used in Asian markets and is known for its sweet, lemony aroma. With bright green and narrow leaves, lemon basil is extremely easy to grow and will flourish if coupled with a warm-watered fish such as Tilapia.
3. Purple Passion Basil
Purple passion basil is another type that will do well in aquaponics. With narrow pointed leaves and a distinctive peppery taste, purple passion basil will compliment whatever salad or pasta you choose to put it in. Additionally, as the plant is purple in color, it’s aesthetically unique and will look great alongside other varieties.
Conclusion
If you’re going to get into aquaponics, basil is a great plant to start with. It’s incredibly easy to grow under the right conditions and it won’t give you a lot of trouble. If paired with the right fish, basil will grow happy and healthy all year long.
