Azolla Farming: Grow Green Gold, Earn More

Azolla is a free-floating aquatic fern that’s gaining popularity in farming due to its use as a nutrient-rich livestock feed, biofertilizer, and green manure, particularly in rice fields. Here’s a concise overview of Azolla farming based on current information.

What is Azolla?

Azolla is a small aquatic plant, often called the "mosquito fern," that floats on water surfaces. It has a symbiotic relationship with nitrogen-fixing cyanobacteria (Anabaena), making it rich in proteins (25–35%), amino acids, vitamins (A, B12, Beta Carotene), and minerals. Its low lignin content makes it easily digestible for livestock such as cattle, poultry, fish, and pigs.

It is also used to boost rice yields by up to 20% when cultivated in paddy fields. In addition, Azolla helps control weeds, reduce water evaporation, and even limit mosquito breeding.

Benefits of Azolla Farming

Livestock Feed – A low-cost, sustainable feed supplement that reduces feed costs and increases milk yield in dairy animals.
Biofertilizer – Fixes nitrogen naturally, enriching soil fertility for rice and other crops.
Environmental Benefits – Reduces CO₂, N₂O, and CH₄ emissions, sequesters carbon, and suppresses toxic algal blooms in water bodies.
Weed Control – Forms a dense mat on water surfaces, preventing weed growth in paddy fields.
Low Investment – Requires minimal resources, making it accessible and profitable for small-scale farmers.

Azolla Cultivation Method

Here’s a step-by-step guide, based on methods like those developed by India’s NARDEP project:

(a) Site Selection
Choose a partially shaded area (about 30% sunlight) to prevent excess heat from damaging the plants.

(b) Pond Construction

Dig a pit (e.g., 6 × 4 feet for small-scale or 2 × 2 × 0.2 meters).
Level the base and line it with a UV-resistant plastic sheet (such as silpauline) or other durable material, securing with bricks or soil to prevent leaks.
Spread 10–15 kg of sieved fertile soil at the bottom, then fill with 10–15 cm of water.

(c) Inoculation

Add 1–2 kg of fresh Azolla culture (sourced from local farmers, KVKs, or online suppliers).
Optionally, add 1–2 kg of cow dung slurry or 20–30 g of superphosphate to boost growth.

(d) Maintenance

Maintain water depth at 10–15 cm and pH between 6.5–7.5.
Cover the pond with a net to prevent debris and provide shade.
Stir the water occasionally to ensure even growth.

(e) Harvesting

Under optimal conditions, Azolla doubles its biomass every 3–5 days.
From a small pond, harvest 1–2 kg daily using a scoop net.
Wash harvested Azolla before feeding to livestock to remove impurities.

Growing Azolla with Fish

Azolla can also be cultivated in fish ponds (e.g., with carp or tilapia), creating a mutually beneficial system.

Benefits – Azolla provides shade, lowers water temperature, and serves as a natural feed for herbivorous fish. In turn, fish waste fertilizes Azolla, enhancing its growth.
Considerations – Avoid overcrowding ponds, as fish may overconsume Azolla. Monitor water quality to prevent excessive nutrient buildup, which could harm fish. A 4 × 8 meter pond is viable for small-scale Azolla–fish integration, provided a balance is maintained to avoid oxygen depletion.

Challenges and Tips

Reddish Discoloration – If Azolla turns red, it’s usually due to excessive sunlight. Increase shading or adjust the covering net.
Pest Control – Azolla is relatively pest-resistant, but insect larvae may appear. Manual removal or introducing small fish can help.
Sourcing Seeds – Obtain Azolla culture from local farmers, agricultural institutes, or online platforms. It is legal to cultivate in most regions, including India.
Commercial Viability – For large-scale production, study market demand (e.g., dairy, poultry, fish farmers). Dried Azolla can be marketed as a feed supplement. Contact local agricultural offices for pricing and buyer networks.

Where to Start?

Small-Scale – A 6 × 4 ft pond can produce about 1 kg of Azolla daily, sufficient to supplement feed for a few animals.
Sourcing – Contact agricultural extension offices, Krishi Vigyan Kendras (KVK), or online suppliers for Azolla culture.
Learning More – Engage with farmer groups or refer to resources such as The Azolla Foundation or Agri Farming for detailed guides.

If you are in a specific region, reach out to agricultural universities or KVKs for Azolla seeds and location-specific advice. For commercial ventures, assess local demand and connect with dairy, poultry, or fish farmers.

Success Stories in Azolla Farming

1. Narayan Reddy’s Experiment in Karnataka

Organic farmer Narayan Reddy, inspired by a 2002 LEISA India article, began Azolla cultivation on his farm. He constructed a simple 2 × 3 × 0.15–0.2 m bed lined with a plastic sheet, secured with soil and concrete for sun protection. About 2–3 cm of stone-free soil was spread at the bottom, and the bed was filled with water. Using cow dung and superphosphate as fertilizers, Reddy inoculated the bed with Azolla culture.

Within weeks, he was harvesting 500–600 grams daily, which he used as livestock feed. This reduced his feed costs significantly. Thanks to Azolla’s high protein content (25–35% dry weight), milk yield in his dairy cows improved by up to 16.25%. His low-cost setup (using local materials) and minimal maintenance made Azolla a profitable venture for his small-scale farm.

2. Commercial Azolla Farming in Odisha

A farmer in Odisha, as reported by Agri Farming, started large-scale Azolla cultivation. They sourced Azolla seeds (available for about ₹200 per kg on IndiaMart) and set up multiple 6 × 4 ft ponds. Each pond produced around 1 kg of Azolla daily, with harvest beginning 2–3 weeks after inoculation.

The harvested Azolla was sold as livestock feed to local dairy and poultry farmers or dried for storage and wider markets. With rising demand for Azolla as both biofertilizer and feed supplement, the farmer tapped into a profitable niche. Though exact earnings weren’t specified, the low input costs (₹200–500 for seeds and pond materials) and daily harvests ensured a high return on investment, especially at scale.