How we grow wonder food spirulina

Five years ago, Luke Harries (pictured) knew nothing about Spirulina, a little know wonder food.

“I’d never heard of it until a businessman friend mentioned it to me. We were talking about trends and what we wanted to do, businesswise. Spirulina stuck on me. I found some of its powder and after taking it for a few months I noticed the difference in my health,” Harries recalls.

After extensive research, he set up a spirulina farm — Tiwani— in Tiwi, Kwale County. The farm is set on an acre with 8 functional ponds.

Spirulina is a type of blue-green algae that people can take as a dietary supplement.

People consider spirulina a superfood due to its excellent nutritional content and health benefits.

Like all farming ventures, setting up the spirulina farm was not a walk in the park.

“When we started spirulina farming, there was no one to point us in the right direction. We were building on hope that it was going to work. I relied on the internet for information. As a result, we wasted money in the initial stages,” he explains.

Given that he was walking a path few have taken, there was no point of referral for knowledge on the same. 

“Unlike other industries like flower farming where there is a lot of expertise and research, with spirulina there is little knowledge and expertise locally, or even research. It is like operating in the dark,” he says.

Ideal growth conditions

Extrapolating from the laboratory into the real world was also a challenge.

“The laboratory conditions for spirulina growth are ideal; it needs light for photosynthesis and does well at high temperatures of between 35 degrees and 37 degrees Celsius. These conditions can be consistently provided in the lab throughout the year, but cannot be controlled in the real world.

“Different times of the year require different processes,” he says of need to adapt to the environment.

For ease of temperature control, given that Kwale is quite hot, he invested in greenhouses.

The greenhouse also protects the cultures from rain, insects and pests.

Right culture

Step by step he has perfected his art. Among the things he has learnt to monitor is the water makeup in the ponds.

“We monitor the nutrient content weekly. We noticed there are times of the year where there is an excess of nutrients in the water which has caused loss of production. This is during the cooler seasons where temperatures are low and spirulina growth slows down.

George Mbakaya, an expert on sustainable agriculture says spirulina will not grow anywhere that has constant low temperature of below 25 degrees.

He says spirulina, though it has great potential, is a sensitive crop that needs to be handled with care. 

“Give it the wrong things at the wrong time, and you risk killing it. That is why Tiwani started with one greenhouse which is now the harvest tank.

I deal conditions

Mr Mbakaya says Spirulina grows in highly alkaline solution of a pH between 8 and 11. The solution is a mix of specific minerals.

There are various different recipes to achieving this solution, depending on your budget and the conditions, says Harries.

The level of the pond and amount of nutrients needs to be maintained by regularly replacing fertilisers and water, says Mbakaya.

“We have had to empty our tanks on several occasions when we tried different mix of minerals that didn’t work,” says Harries.

Mbakaya advises anyone interested in this line of business to have access to credit.

To avoid costly blunders, one should engage someone who has successfully grown the crop.

If you invest in a greenhouse, chances of success are higher.

Harries says a 20m by 2m compartmented greenhouse costs Sh500,000 to construct and gives you 350gm dry spirulina daily.

Aeration

From one tank to eight, Tiwani has had to develop its own systems for maximum spirulina production.

“We developed a new tube system for the spirulina growth. The issue we have with the system is the angling of the tubes. We should have placed them at an angle (as opposed to flat) so the spirulina drains out completely once it flows through the tubes,” says Harries.

Investing in power is also key.

Harries says they also had issues with the electric powered motor used to pump the spirulina along the tubes.

“We had to find one that doesn’t produce too much heat or have too much power. Unlike other single-celled algae, spirulina contains no cellulose in its cell walls, making it delicate and easy to destroy.”

At Tiwani, the spirulina in tanks is still stirred manually every hour.

“Spirulina tends to come to the surface to get maximum light and heat. This blocks other spirulina filaments from accessing the same and hence reducing rate of photosynthesis for the hidden spirulina,” says Harries.

Drying

Value addition guarantees farmers more returns and as with other agricultural produce, spirulina can also be processed to finished products.

Since it is not commercially viable to sell frozen Spirulina, Tiwani dries, mills and makes capsules.

Drying elongates the shelf life to up to five years, if stored correctly; in heat sealed opaque bags, out of direct sunlight.

“The presence of intense light can bleach or destroy some of the proteins and chlorophyll,” says Harries.

Tiwani farm dries spirulina in a dark room, using solar energy at between 50 and 55 degrees Celsius for about four hours.