Aquaponic farming allows you to grow your plants and fish at a very fast rate. Since the plants have unlimited access to nutrients in their roots, they can grow up to 25% faster compared to being planted on soil. Even the fish cultivated in the system also tend to grow quickly as soon as they’ve adapted to their surroundings.
How fast do plants grow in aquaponics?
Compared to soil-based farming, plants grow considerably faster, healthier, and larger with the aquaponics system. This is because the plants have round-the-clock access to nutrients. Take lettuce for example. The usual period for growth is around two months but with the aquaponics system, it typically takes only one month. In some tests, vegetables and herbs have grown even up to four times faster with an aquaponics system compared to a hydroponics system.
In some other tests plants have grow up to 25% faster in an aquaponics system which is also an admirable feat. Also, many studies attest to the fact that plants in a soilless system grow larger and they’re also more likely to survive compared to when planted in soil. The flavor quality of plants in an aquaponics system is also outstanding and at least on par with the soil-grown ones.
Ideal plants to grow with the aquaponics system include beans, zucchini, squash, broccoli, peppers, cucumber, peas, spinach, basil, thyme, cilantro, sage, lemongrass, wheatgrass, oregano, parsley, strawberries, watermelon, cantaloupe, tomatoes, and most garden varieties of flowers.
Here are some popular plants and vegetables that are grown in an aquaponics system with some info on their growth and harvest time:
Tomatoes
Tomatoes grow fast in an aquaponic system given the right conditions. There is an observed growth in two weeks and fully developed flowers will develop at around four weeks from planting. Harvest time is around 8 weeks or around 2 months. The best methods to grow it is through the gravel bed approach and deep water culture.
Cucumber, zucchini, and squash
These trellis plants grow fast in an aquaponic system and the best varieties are the self-pollinating ones. These plants are commonly grown by aquaponics farmers and harvest time is at around two months.
Lettuce
Lettuce is a good option to cultivate if you’re just starting with aquaponics. It grows quickly and with the right method and conditions, you can harvest in 4 to 5 weeks from planting. The recommended methods to plant it is through the floating raft or deep water culture and with the use of grow beds. It thrives best in water temperature of between 70 and 74 degrees Fahrenheit and a pH level that’s between 5.8 and 6.2.
Kale
Kale grows fast in an aquaponics system and ready for harvest in just 6 weeks as opposed to 3 -months of growth if planted on soil. The best way to grow kale is through the tower or raft system and it’s usually grown in cooler months with a preferred pH of between 6 and 7.5.
Cabbage
Given the right conditions, cabbage grows rapidly in an aquaponic system and it’s ready for harvest in 80 to 180 days. It favors temperatures between 45 degrees Fahrenheit and 75 degrees Fahrenheit and a preferred pH of 6.2 to 6.6. This vegetable loves the sun so it’s best to place it in a sunny position if possible. Rainbow trout fish is a good match for cabbages in an aquaponics system because they both thrive in a cold climate.
What are the factors affecting plant growth in aquaponics?
Aside from the unlimited access to nutrients, there are other contributing factors why plants grow fast in aquaponics. Here we list the factors that affect the plant growth in this farming system.
- Nutrients – The plants grow fast because of the essential nutrients that they get from the fish waste which is a good source of plant food and nutrients including phosphorus, nitrogen, calcium, potassium, and sulfur. These are all available all the time allowing the plants to grow faster and healthier.
- Water pH level – The suggested pH level is 5.5 to 7.5 and if the pH level exceeds the normal level the plants wouldn’t be able to absorb the nutrients. However, this will depend on a variety of plants and fish in the system.
- Dissolved oxygen in water – Oxygen is essential to avoid fungus growth and root rot and the recommended amount of dissolved oxygen should not be greater than 3 mg/liter.
- water temperature – The recommended temperature is between 18 to 30 degrees Centigrade although leafy green vegetables can thrive at temperatures between 14 to 20 degrees Centigrade.
- Light – Plants in an aquaponics system should be placed in an area that has direct access to sunlight for its photosynthesis requirement.
- Planting design – Planting design and spacing are essential to ensure that all the plants receive the necessary nutrients.
- Balance of fish and plants – There should be a balanced ratio between plants and fish so that nutrients are well-distributed.
- Biofilter- A biofilter or nitrification process is needed to convert the fish waste into a natural fertilizer with the help of bacteria that convert ammonia into nitrates.
Conclusion
Aquaponics is gaining popularity among gardeners and farmers because it’s many benefits compared to traditional farming. It’s also sustainable and it shows great promise in helping to address the world’s increasing food requirements in the coming years. Plants grow faster at a rate of 25% more compared to those planted with a traditional land-based farming method. Moreover, the plants are healthier and larger because they have round-the-clock access to essential nutrients and in consideration of other factors like water pH level and temperature as well as light and the planting design.