Group Title: TropSoils field research brief ;, 34
Title: Farmer and crop responses to different sources of fertilizers : : a farmer-managed study on home gardens
Full Citation
Permanent Link:
 Material Information
Title: Farmer and crop responses to different sources of fertilizers : : a farmer-managed study on home gardens
Series Title: TropSoils field research brief ;, 34
Physical Description: 9 leaves ; 28 cm.
Language: English
Creator: Agus, Fahmuddin.
Soil Management Collaborative Research Support Program.
Lembaga Penelitian Tanah.
Publisher: Soil Management Collaborative Research Support Program, North Carolina State University,
Publication Date: 1987
Subject: Fertilizers -- Research -- Indonesia.
Soil management -- Indonesia.
Farmers -- Attitudes. -- Indonesia
Spatial Coverage: Indonesia.
General Note: Caption title.
General Note: "January 1987."
General Note: At head of title: Centre for Soil Research.
 Record Information
Bibliographic ID: UF00080610
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 162136243

Full Text


Centre for Soil Research; J Ir. H. Juanda 98; Boror: Indonesia (0251) 23012
Contact: TROPSOILS; Box 02; Sitiung 1A; Sumatera Barat

TITLE: Farmer and Crop Responses to Different Sources of
Fertilizers: A Farmer-managed Study on Home Gardens

EXPERIMENT NO.: 3108 and 3508
RESEARCHERS:'Fahmuddin -Agus, Carol J. Pierce Colfer
Stacy Evensen and Sholeh
1) Observing farmers' responses to different sources of
fertilizers (organic and inorganic),
2) Introducing other varieties of crop that can be produced on
home gardens, and
3) Comparing crop responses to different kinds of fertilizers in
relation to costs.
A fourth objective---working collaboratively with women farmers,
in a more effective manner---was not realized.
This experiment was initiated with 13 cooperator farmers in
Sitiung V (Aur Jaya) and in Sitiung I (Piruko). Each farmer was
considered to be a farmer-managed replication. The soil in
Sitiung I is predominantly Inceptisol and -in Sitiung V Ultisol.
The fertility of plots within' each farmer's field and from one
farmer- to another was quite variable, due to the-different. -.
methods of soil-management and to the various crops that had been
planted on any particular spot.
Treatments tested in this study were:
Treatment 1 = Control; no fertilizer application.
Treatment 2 = 10 t/ha of barnyard manure (broadcast).
Treatment 3 = 10 t/ha compost (broadcast)
Treatment 4 = (kg/ha) 100 Urea, 125 TSP, 125 KCI, and
80 kieserite (MgS04), (broadcast)
Treatment 5 (5 replications) = 25t/ha fishpond sediment
(averaging 73 % water content on weight basis; broadcast)
These treatment were arranged in a Randomized Complete Block
design with 7 Javanese farmer-managed replications in Sitiung I
and 6 in Sitiung V (all Sundanese).


Chili (Capsicum annuum L.) was planted in September 1985,
and bambara groundnuts (Voandzeia subterrania) were planted in
March 1986. Chili seedlings, bambara nut seeds and pesticide
were distributed, in addition to inorganic fertilizers, compost,
and in Sitiung V, barnyard manure. Any farmers' responses,
complaints and comments were recorded, in addition to a pre-
planned set of parameters.


I. Farmers' responses to the crops

1. Chili
When the farmers were asked about what kind of crop they
would like to grow for the experiment, their initial response was
almost unanimous: "It's up to you." Since one of our main
interests was farmer input, we tried again. We presented several
crops such as chili, tomato, bambara groundnuts, spinach, wing
bean, etc., to the farmers as possibilities, and asked them to
choose again. This time they chose chili.

Chili is the most common spice (appetizer), normally eaten
by the transmigrants with rice and vegetables (transmigrants
don't eat much meat on a daily basis). The amount of chili
consumption is variable among individuals, families, and ethnic
groups, but from a global perspective, is probably high for
almost everyone in West Sumatra. Despite its ubiquity in the
diet, it is not widely grown among transmigrants except for a few
Sundanese who were were growing lots of it in large plots in
their home gardens in Sitiung V in 1983-84. Some simply preferred
growing other food crops, and some said they had no experience
growing chili and hadn't thought of doing so. They were
interested in trying it, given our provision of supplies and

From a nutritional viewpoint, chili contains mostly-y-
carbohydrates and vitamins (especially vitamti A). Although its
hot taste requires that it be eaten in fairly small amounts, it
may provide small amounts of Vitamin A (important, since
blindness caused by vitamin A deficiency is a widely recognized
"Indonesian health problem). Its price fluctuates widely. In early
1984 its price was as high as Rp. 4,000 per kg. This figure can
also drop as low as Rp. 500 per kg (in February 1986, US $ 1 =
Rp. 1126)

2. Bambara groundnuts
The method of choosing this crop was similar to the way we
chose chili. Only after giving some alternatives, did the farmers
spontaneously choose bambara nuts. The reason being was that they
just like the crop and even though a few of them in Sitiung V
planted it, it was difficult for them to find the seed.

Bambara groundnuts are normally planted only in home
gardens, by a few Javanese and Sundanese transmigrants. Usually
only small amounts of land are devoted to this crop, and its
purpose is home consumption. The market for this crop is
undeveloped in Sitiung, since most of the indigenous communities,
where the markets are centered, are completely unfamiliar with
it. This, as well as the difficulty in getting seeds, may be the
reason that farmers don't grow it in large quantities.

However, although the local market for bambara groundnuts is
limited now, the nutritional benefits of its cultivation make it
an excellent home garden crop. Bambara groundnuts are a rich
source of protein, carbohydrates, and iron and can substantially
enhance the family's diet. They are also easy to harvest and

II. Farmer response to treatments

Most cooperator farmers readily recognized the usefulness of
inorganic fertilizers, compost, and barnyard manure. 'Many of
them were curious when we introduced the use of fishpond
sediment. They anticipated that it would not be very different
from soil, and would require a lot of work to apply.
Furthermore, only half of the cooperator farmers had fishponds on
their home gardens. Many farmers even preferred the control
treatment to the sediment treatment. The farmer's practice of
neither feeding their fish nor fertilizing their ponds (Dudley
and Hidayat 1986) meant that the pond sediments were usually low
in nutrients. This low nutrient content was reflected in low
crop yields (Table 2).

At the time of this study, inorganic fertilizer was the most
common soil amendment in Sitiung VC. This was primarily because
the farmers did not have ruminants which could supply large
amounts of manure. Another important factor was that government
fertilizer recommendations focused almost exclusively on
inorganic fertilizers. Despite not having a good source of
manure, the farmers recognized its value. Manure use-is very
common on Java, where these farmers learned to farm.

Compost is a kind of organic fertilizer which needs some
work prior to application. This treatment was considered to be
'time consuming. However, most of the farmers also believed that
this amendment would be good for crops, in general. Their
response leads us to believe that there is still a hope for
composting, if we can introduce a simplified method of compost
preparation. A few farmers prepared compost in a garbage well.
Separating plastic and other nonweatherable materials, the
farmers dumped garbage from the kitchen and from the home garden
into the well. They let the material rot and used it whenever
they wanted it. Although this is a very simple method, it is
impossible to produce a large amount of compost this way, so only
a limited kind and number of crops can benefit from it.

In Sitiung I A, manure was used almost as widely as
inorganic fertilizers. Manure might even surpass the popularity
of purchased fertilizers there. Almost every family in Sitiung I
had ruminant livestock. Manure, along with inorganic
fertilizers, was often applied, particularly to paddy rice.

There were more trees in Sitiung I home gardens, probably
because of longer residence. Selected kinds of trees in Sitiung
I had also been fertilzied with manure, dependent on its
availability. Farmers have less open space and thus devote less
attention to annual crop production. Trees, like coconut, clove,
jackfruit and coffee dominated these home gardens. Part of each
farmer's home garden was devoted to a stable for cattle and goats
and, on some, a fishpond or two. Almost every farmer raised
chickens. Sitiung I farmers showed less interest in compost than
did Sitiung V farmers saying that since they had manure, there
was no need to bother with making compost.

Even if there are more fishponds in Sitiung I, farmers still
think applying the fishpond sediment would require a great deal
of work. Although they occasionally dig out the fishponds, the
sludge is simply piled along the edge of the ponds. Coconuts and
other trees grew along the edges of many fishponds. Table 1 shows
the farmers' rankings of the various treatments.

III. Crop response to treatments

Statistical analysis in Table 2 shows that, for chili,
manure, inorganic fertilizers, and compost gave significantly
higher yield than either the fishpond sediment or the control.
(NOTE: The fishpond sediment treatment had fewer replications
than the others)

For bambara groundnuts, inorganic fertilizers produced the
highest yield of nuts. Compost and manure were not significantly
different from each other, but they were significantly lower than
inorganic fertilizers, and significantly higher than either the
control or the fishpond sludge.

IV. Economic realities

Since there were significant effects of treatments on
yields, the data is more meaningful if economic analysis is done
in addition to statistical analysis. Tables 3 and 4 show the
summary of partial budget analysis. Table 3 shows that for chili,
inorganic fertilizer application, at the rate applied in this
treatment, gave a very promising MRR (1332 %). This means that
when we invest an additional Rp. 61,000 to apply the inorganic
fertilizer, we receive 1332 Z Rp. 61,000 more in addition to
the Rp. 61,000 we invested. And if more money (Rp. 55,000) is
invested to change inorganic fertilizer treatment to manure
treatment, we will receive 283 Rp. 55,000 more in addition to
the Rp. 55,000.

From Table 4, it can be seen that inorganic fertilizer
application was the only economically viable treatment (with iRR
of 750 %). Other treatments were dominated by this treatment.
This means that additional money invested for other treatments
did not give an increase on net benefit. However, long term
effects of fertilizer use versus organic matter use on soils has
not been studied.


1. Chili and bambara ground nuts seem to be promising crops
for cultivation on home gardens. These two crops gave significant
responses to barnyard manure, compost, and inorganic fertilizers
at the rates applied in this trial. The application of fishpond
sediment (from ponds with such low levels of management and at
the rates of sludge applied) did not significantly improve yields
over no soil amendment at all (the control treatment). Farmers
also preferred the first three treatments over the other two.

2. From the viewpoint of production only, manure, inorganic
fertilizers and compost gave good yields to chili and bambara
nuts. However if cost-benefit is taken into account, we would not
recommend these treatments equally. For chili, manure application
was the most economical (assuming the "Iinimum Rate of Return of
100 %). Inorganic fertilizer application is still recommendable
in cases of capital/labour shortage for manure. For banbara nuts,
a inorganic fertilizers application was the most economical.
Statistically, manure and compost treatments were significantly
higher than control and fishpond sediment treatments. However,
since they needed higher input and resulted in less net benefit
than inorganic fertilizer application, these two treatments were
not economical.

Table 1. Farmers' preference to different sources of
Rank Number of farmers preferring various treatments

Treatment 1st 2nd 3rd 4th 5th
Control 0 0 0 11 2
Compost 2 1 9 0 0
Manure 6 5 2 0 0
Fertilizer 5 7 1 0 0
F. Sediment 0 0 0 2 3

Table 2. Effects of different sources of nutrients on chili and
bambara groundnut production.
Treatment Average Yield (kg/ha) *)

Chili Bambara nuts
Control 860 b 2900 c
Compost 1677 a 3860 b
Manure 1883 a 3810 b
Fertilizer 1682 a 4180 a
Fishpond sediment 875 b 2960 c
*) Average of thirteen replications, except for the
fishpond sediment treatment which is average of
seven treatments
*") Any two means having a common letter are not signi-
ficantly different at the 5 % level of significance using

CV = 44 %
CV(chili) = 28 %
(bambara nuts)
Table 3. Summary of partial budget calculation for chili
under this experiment *)
Treatment Ay (kg/ha) GB (Rp) NE (Rp) TCV (Rp.) KRR (Z)
Control 731 913,750 913,750 0
F. sediment 744 930,000 S70,000 60,000 d
Fertilizer 1,430 1,787,500 1,726,500 61,000 1,332
Manure 1,601 2,001,250 1,885,250 116,000 288
Compost 1,425 1,781,250 1,583,250 198,000 d
*) See Appendix 1 for the detail of partial budget analysis
"d" in the column of MRR means dominated. A treatment is
dominated when its TCV is higher but its MB is lower then
another treatment.

Table 4. Summary of partial budget calculation for bambara nuts
under this experiment *)

Treatment Ay (kg/ha) GB (Rp) NB (Rp) TCV (Rp.) HRR (Z)

Control 2,465 616,250 616,250 0
Fertilizer 3,553 880,250 856,250 32,000 750
F. sediment 2,516 629,000 569,000 60,000 d
manure 3,293 823,250 707,250 116,000 d
Compost 3,281 820,250 622,250 19C,000 d

*) See Appendix 1 for the detail of partial budget analysis
"d" in the column of MRR means dominated. A treatment is
dominated when its TCV is higher but its ND is lower then
another treatment.
Note: US $ 1 = Rp. 1,126.
Ay = Adjusted yield
GB = Gross benefit
NB = Net benefit
TCV = Total cost-that vary
,RR = Marginal rate of return

Appendix 1. Partial budget analysis for chili and banbara nuts
under this experiment

This appendix is to explain Table 3 and Table 4. Further
explanation on the way we analyze partial budgets can be studied
from Harrington, 1C5.

1. Adjusted yield. Yield was adjusted because researcher managed
harvest areas were very small (10 m2). This adjustment was done
based on researchers' judgement of yields biased if this
experiment were done in a large area. In this experiment, yield
was adjusted 15 % downward or:

Adj. Y = .85 Average yield

Average yield is the average of yields per locations as in
Table 2.

2. Gross benefit was obtained from the following formula:

GB = Adj. Y Field price
Field price (Rp/kg) = Karket price Yield related cost
Yield related costs are such costs as cost of harvesting,
shelling, transportation, drying, etc. This cost is very
dependent on the amount of yield.

a. Field price for chili:
market price = Rp. 2,000/kg
Yield related costs:
Harvest (opportunity) cost = Rp. 215/kg
Transportation and handling cost = Rp. 35/kg

Damage in storage and transportation = 25 % Rp 2000
(estimation) = Rp. 500/kg
All yield related costs = Rp. 750/kg
Field price = Rp. 1250/kg
b. Field price for bambara nuts:
ilarket price = Rp. 500/kg
Yield related costs:
Harvest (opportunity) cost = Rp. 50/kg
Shelling (opportunity) cost = Rp. 50/kg
Transportation and handling cost = Rp. 25/kg
Damage in storage and transportation = 25 % Rp 500
(estimation) = Rp. 125/kg
All yield related costs = Rp. 250/kg
Field price = Rp. 250/kg

3. Net benefit = Gross benefit Total cost that vary.

4. Total costs that vary (TCV) is the difference in cost between
each treatment and control treatment. Cost that vary can come
from the fami-ly. This kind of cost is termed opportunity cost.

TCV (control treatment)= 0

TCV (compost treatment) :

Compost in this treatment was made from 7.5 tons of grass
and 5 tons of barnyard manure for a hectare of land. Forty two
man days were needed-for grass (shrub) collection and compost
preparation. tle also used wooden boxes for the compost
preparation. The wood used for the box was the unsaleable wood
cuttings from a nearby sawmill, so that the (opportunity) cost
for a box was Rp.6000. Eight boxes of this kind were needed to
fulfill the need of a hectare of land. Eight mandays were needed
to apply compost. Five tons of manure had the (opportunity) cost
of Rp. 50,000.

TCV for compost was Rp. (50*2,000 + 8*5,000 + 50,000)
= Rp. 19,000.

TCV (manure treatment):
10 tons of manure =Rp. 100,000
(Opportunity) cost of application (including carrying to the
field) was equivalent to 3 man days = Rp. 15,000.
TCV manure = Rp. 116,000.

TCV (Fertilizers):
1. Chili
100 kg Urea @ Rp. 100/kg = Rp. 10,000.
125 kg TSP @ Rp. 100/kg = Rp. 12,500.
125 kg KC1 0 Rp. 100/kg = Rp. 12,500.
80 kg MgS04 0 Rp. 300 = Rp. 24,000.
(Opportunity) cost for application 1 man day = Rp. 2,000.
TCV fertilizer = Rp. 61,00G

2. Bambara groundnuts.

No MgS04 was applied for bambara groundnuts and residual Mg
from the first crop was neglected. Urea was applied at the rate
of 50 kg/ha.
50 kg Urea @ Rp. 100/kg = Rp. 5,000.
125 kg TSP @ Rp. 100/kg = Rp. 12,500.
125 kg KC1 @ Rp. 100/kg = Rp. 12,500.
(Opportunity) cost for application 1 man day = Rp. 2,000.
TCV fertilizer = Rp. 32,000.

TCV (Fishpond sediment treatment):
Only (opportunity) cost for labor can be calculated since
there is no market for fishpond sediment. (Opportunity) cost for
digging and applying the sediment was equivalent to 30 man days =
Rp 60,000. This is TCV for fishpond sediment treatment.

5. Marginal rate of return (1iRR) is the percentage of NB increase
divided by TCV increase. Investment can be done if ilRR exceeds
minimumm Rate of Return (iRR).

5. Minimum Rate of Return is the sum of Cost of Borrowed Capital
and Returns to management. In Indonesia, as well as in other
countries where capital is scarce, the MRR is most probably 100
Z or so.

University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs