AGFAX: March 2010
Combining fertilisers for maximum yield
Moses Munthali and Pansipowuma Ngoni: Crop scientist, Chitedze Research Station, Malawi and Maize farmer, Dowa, Malawi
Summary:
Recent field trials in central Malawi suggest that using a half-half combination of organic and chemical fertilisers in maize production gives higher yields than using entirely one or the other. This is potentially good news for farmers who only have limited quantities of organic manure and cannot afford to buy sufficient chemical fertiliser for their cropping area. Crop scientist Moses Munthali describes the trials and maize farmer Pansipowuma Ngoni talks about her experience of combined fertiliser use, with George Kalungwe.
Suggested introduction:
Farmers are frequently advised to use fertiliser on their fields to improve soil fertility and increase their crop yields. But obtaining and using fertiliser is not easy; animal manure or compost is bulky and difficult to obtain in large quantities, and chemical fertilisers are expensive.
But there is some good news. Recent crop trials in Malawi suggest that using a combination of organic and inorganic fertiliser can give farmers the best results. George Kalungwe spoke to crop scientist Moses Munthali, and asked him to explain more about the trials, and what they have revealed.
Tape in:
What we did was we used...
Tape out:
...there is a still a difference.
Closing Announcement:
George Kalungwe reporting from Dowa district in Malawi.
Making the most of it:
Farmer Mrs Ngoni puts organic manure in trenches and planting stations before planting, and adds chemical fertiliser later, once the crop is growing. What experiences do your listeners have with this kind of technique? Do they have other suggestions for how to combine organic and inorganic fertilisers for the best results? What other farmer experiments are leading to better yields?
Further information:
Moses Munthali - munthalimw@yahoo.co.uk
Transcript
Munthali
What we did was we used the compost manure alone and then we also used the chemical fertiliser alone and then we also combined. We use half nitrogen from the chemical fertiliser and then the other half from the organic fertiliser. So from our findings we got 3.5 tons of maize grain yield from the organic fertiliser and then where we used only inorganic fertiliser we got 4.6 tons. While in combination of the chemical and organic we got 6.6 tons per hectare. Which means if you just use inorganic alone or organic alone you are getting less than two tons but if you combine you are getting two point something and above.
Kalungwe
Now what prompted you to conduct such type of a research?
Munthali
If you look at the organic fertilisers they supply most of the nutrients but also if you look at the farmers now in terms of the quantities, to apply the same rate you require a lot of quantities. For example if you are to apply 92 kilogrammes of nitrogen per hectare then you have to apply maybe more than eight tons or even 10 tons or 12 tons depending on the composting materials that you are using. So most farmers they cannot afford to produce such quantities of manure. That is why we wanted to see if we can use possibly, maybe reduce the quantities, the quantities that farmers can manage to produce. But at the same time also, if you look at the chemical fertiliser, they are very expensive. So farmers are able to get maybe one bag or two bags. So we wanted to see if we can make a combination so that we should get the same yield per hectare in order to maximise the production.
Studio
The combined use of organic manure and chemical fertilizer can indeed make a difference, if the views of one farmer from Malawi's central region are anything to go by. Mrs Pansipowuma Ngoni from Dowa district uses a combination of organic manure and chemical fertilizer in her maize garden. But how long has she been doing this?
Ngoni
(Vernac) I have been using organic manure and chemical fertiliser for three years.
Kalungwe
Why did you decide to use organic manure combined with chemical fertiliser in the same field?
Ngoni
(Vernac) I did this because sometimes you lack money and then when you apply manure, organic manure you can still have something from your field.
Kalungwe
You are talking of reducing the cost incurred in terms of purchasing fertiliser but what are the other advantages which you have seen when it comes to the combined use of manure and chemical fertiliser?
Ngoni
(Vernac) We find that most of the times when you apply manure it is like you are retaining soil fertility in the soil and then your crops are usually healthy.
Kalungwe
Do you follow any formal method when it comes to the combined use of organic manure and chemical fertiliser in your field or do you just do it anyhow?
Ngoni
(Vernac) We have some methods that we follow. We apply organic manure in the trenches or sometimes on the planting stations and then later on when we plant our crops, that is when we apply chemical fertiliser.
Kalungwe
Are there any challenges which you face when doing this?
Ngoni
(Vernac) There are usually some challenges when you want to transport your organic manure from home because we usually do this at home and we want to transport it from home to the gardens. It is usually a long distance and sometimes you are hurt in the process. In some cases you have like broken glasses in the manure and when you are trying to get it out from wherever you made the manure you get hurt.
Kalungwe
Lastly how much money do you think you save because of following this process?
Ngoni
(Vernac) Usually I do not budget on how much money I save after I have combined the use of organic manure and chemical fertiliser but I see the difference because when you apply organic manure the bags that you apply of chemical fertiliser will be less than when you only use chemical fertiliser in your garden. So I think there is a still a difference. End of track
