- Azolla is a Miraculous fern for nitrogen fixation & sustainable cattle feed
- Azolla is a free floating fern and can be grown in ponds, pits, tanks, etc.
- Azolla can be very easily cultivated in a pit with depth of 20 centimetres.
- Azolla mother culture 250 g per sq mt.
- Labour for making trenches
- 5 kgs sieved soil per sq meter
- Poly sheet
- Poly net
- Few gunny bags
- Cow dung (4-5 days old) 1.5 kg per sq m
- Neem cake 125gm per sq meter
Azolla cultivation pit can be prepared using the following options
- Dig a trench and Arrange bricks in a rectangle or square so that a pit is formed between the four sides.
- Construct a concrete pit, in this case directly go to step 5
- The pit should be 20 cms deep.
- Typically you can go for a pit with 2.5 x 1.5 x 0.2 m dimension.
- This will help in harvest and maintenance.
- Have round edges avoid any sharp edge in the corners.
- Level the floor and remove any stones.
- There should be no slope inside the pit.
- Place some gunny bags on the floor
- Cover the pit with UV stabilized poly sheet or tarpaulin sheet.
- Ensure that there is no wrinkle left.
- Also, the edges of the sheet should be well covered with soil so that the sheet remains tight and is not loosened when water is poured into the pit.
- Spread sieved soil on the floor evenly
- Make a slurry by mixing cow dung, neem cake & some water and sprinkle it evenly on the soil in the pit.
- Now fill the pit with water such that water depth of minimum 10 cm is achieved.
- Fill the water cautiously and ensure that the soil does not get concentrated in one corner or area.
- After the water is settled remove the layer of foam and scum that are formed.
- Now add the Azolla mother culture to the pond.
- The Azolla mother culture is nothing but Azolla fern from some existing pit.
- This can be purchased from any existing Azolla cultivator or from agriculture university.
- Place poly net on the pit.
- Azolla will spread @ 400 g per sq m.
- Azolla will cover the entire bed and form a mat within 1 week.
- After 1 week the harvesting of Azolla fern can begin.
- Daily 400 g per sq m should be harvested this will avoid over-crowding of the fern.
- Azolla should be harvested using sieved plastic trays.
- The fern should be washed properly in clean water two to three times to remove the cow dung smell.
- The left over water after washing (Azolla Wash) can be used as bio-manure for plants.
- Azolla can be used as cattle feed.
- The washed Azolla should be mixed with feed concentrates in 1:1 ratio.
- 1 – 1.5 kg of Azolla can be fed to the cattle every day.
- In case of excess, Azolla can be dried and stored.
- This dried azolla can also be fed to cattle.
Dried Azolla can be used as bio-manure in the farm. Azolla is a very good source of nitrogen.
- It is important to keep Azolla at the rapid multiplication growth phase with the minimum doubling time.
- Therefore biomass (around 200 g per square meter) should be removed every day or on alternate days to avoid overcrowding
- About 1 kg of cow dung should be added once every 5 days in order to maintain rapid multiplication of the Azolla and to maintain the daily yield.
- The temperature should be kept below 25 °C.
- If the temperature goes up the light intensity should be reduced by providing shade.
- If possible, it is best to place the production unit where it is shady.
- The pH should be tested periodically and should be maintained between 5.5 and 7.
- About 5 kg of bed soil should be replaced with fresh soil once in 30 days. To avoid nitrogen build up and prevent micro-nutrient deficiency.
- 25 to 30 percent of the water also needs to be replaced with fresh water once every 10 days. To prevent nitrogen build up in the bed.
- The bed should be cleaned the water and soil replaced.
- New Azolla inoculated once every six months.
- A fresh bed has to be prepared and inoculated with pure culture of Azolla, when contaminated by pest and diseases.
- The Azolla should be washed in fresh water before use to remove the smell of cow dung.
- The cost preparing 1 pit of Azolla of size 2.5 x 1.5 x 0.2 m is about Rs.1800/-.
- Overall cost of Azolla harvest is Rs.0.65 per kg.