Conservation Agriculture Practices and Adoption by Smallholder Farmers in
Zimbabwe
By
Mazvimavi, Kizito; Ndlovu, Patrick V.; Nyathi, Putso; and Minde, Isaac J.
Poster presented at the Joint 3rd African Association of Agricultural
Economists (AAAE) and 48th Agricultural Economists Association of South Africa
(AEASA) Conference, Cape Town, South Africa, September 19-23, 2010
Conservation Agriculture Practices and Adoption by Smallholder Farmers in
Zimbabwe
1
Kizito Mazvimavi , Patrick V. Ndlovu, Putso Nyathi and Isaac J. Minde
Abstract
This study is based on a panel survey interviewing 416 farmers practising conservation agriculture for at least
five cropping seasons. Farmers obtained higher yields on conservation agriculture plots than on nonconservation agriculture ones. The mean maize yield on conservation agriculture was 1546 kg/ha compared to
970 kg/ha for non-conventional draft tillage plots across all 15 districts. However, the contribution of
conservation agriculture to total household food security requirements was limited due to small plot sizes. Labor
and land still remains a major challenge that limits the expansion of conservation agriculture area. Winter
weeding remains a challenge, with 63% of farmers practicing it. Application of residues is still limited (56% of
farmers practising it). Fertilizer application is largely dependent on access to free fertilizer. The survey results
show that the 78 % of the respondent farmers were initially selected by the NGOs and were provided with inputs
such as seed and fertilizer. The other 22% of the farmers in the sample were selected as spontaneous adopters,
who did not initially receive any NGO support to implement conservation agriculture practices. Eleven percent
of the interviewed farmers had stopped conservation agriculture practices by the 2008/09 cropping season due to
withdrawal of input support by NGOs. Research should continue to explore different recommendations for
different areas as farmers face dynamic agro-ecological and soil environments. Conservation agriculture should
not be introduced as a blanket technology for all areas, but should be flexible and adaptable to local conditions.
Key words: conservation agriculture, planting basins, yield gains, adoption labor, and fertilizer
1. INTRODUCTION
Close to half of Zimbabwe’s population – about 6 million people − are currently food and
nutrition insecure (UN, 2009). The key reasons for this state of affairs are the continuing low
agricultural productivity, deteriorating soil fertility (Donovan and Casey 1998, Mupangwa, et
al., 2008), dysfunctional input and output markets (Jama and Pizzaro, 2008) and the
unfavorable macro-economic environment. Smallholder farmers in the semi-arid regions are
most affected by this situation. In Zimbabwe, the response to this crisis has been the widescale relief distribution of food aid and direct agricultural input assistance without an exit
strategy for sustaining some of the new technologies promoted within the context of relief aid
(DFID, 2009). This has led to a call on a need to focus on relief assistance that targets
sustainable crop production techniques that also aims at improving soil fertility and improve
on environment protection. One technology option for promoting soil fertility and water
management has been the conservation of soil water, nutrients, and farm power using a
variant of conservation agriculture techniques.
In Zimbabwe, conservation agriculture (CA) and conservation farming (CF) have been
clearly differentiated. Digging planting basins and following principles like mulching and
crop rotation is termed conservation farming while conservation agriculture encompasses all
other minimum tillage methods like rippers and knife rollers and the principles of mulching
and crop rotation and integrated pest management apply (Twomlow et al., 2008). The only
difference is the tillage system; conservation farming is part of conservation agriculture. An
increasing number of non-governmental organizations (NGOs) through funding from
1
Author for Correspondence +263-383-311/7 fax +263 383 253 or 307. Email: K.Mazvimavi@cgiar.org
International Crop Research Institute for the Semi Arid Tropics (ICRISAT). P.O Box 776, Bulawayo,
Zimbabwe
1
multiple donors are now promoting conservation agriculture and the package has recently
been accepted by the government as a group of technology interventions that have the
potential to sustainably increase yields of a wide range of crops by resource-poor farmers
even in drier agro-ecological regions. Farmers across Zimbabwe have shown a growing
interest in the conservation agriculture technology with evidence of yield gains of between 10
and more than 100% depending on input levels and the experience of the farm household
(Mazvimavi et al., 2009). Cases of spontaneous adoption are being observed in areas where
demonstrations and training programs have been well supported by NGOs and research
institutes.
The conservation agriculture impacts achieved in improving food security for poorer farmers
in the semi-arid region of Zimbabwe need to be protected, sustained, and promoted so that
more smallholder households benefit from the technology. This study aims at assessing the
impact of this multi-year donor-funded program and determines how conservation agriculture
using planting basins as the tillage method can contribute to sustained gains in food security
and improve livelihoods of rural farm-based communities. The study will compare the
relative success of farmers in adopting different components of conservation agriculture
technology over time; and assess the socioeconomic impacts of conservation agriculture
technologies to vulnerable farm households.
2. METHODOLOGY
The study is based on a panel survey approach that started in 2006/2007 and repeated in
2007/2008 and 2008/2009. This paper is based on data from the 2008/2009 panel study
carried out in the months of March to May 2009.
2.1.
Study sample
The study was implemented in 15 districts of Zimbabwe where different NGOs under the
Department for International Development’s (DFID’s) Protracted Relief Programme (PRP),
European Union (EU), and European Commission Humanitarian Aid Office (ECHO) funding
have been promoting CA over the past five years. These districts are Bindura, Binga,
Chirumhanzu, Chivi, Hwange, Insiza, Mangwe, Masvingo, Mt. Darwin, Murehwa, Chipinge,
Gokwe South, Seke, Nkayi, and Nyanga (Table 1). A total of 416 households were
interviewed in the 15 districts through a household questionnaire.
2.2.
Yield Measurements
Yield measurements were taken from 10m x 10m sub-plots marked in both CA and non CA
plots (and, in most instances, whole plots). Farmers were given empty 50kg bags to measure
their harvests. Each farmer was asked to count the number of 50kg bags of unshelled cobs
and/or grain upon harvesting from the plots. This was because the crops had not matured
enough for harvesting at the time of the survey. When the harvest data was collected, bags of
cobs or grain were weighed in order to determine the actual yield from the plots.
2
Table 1. Number of farmers interviewed in 2009 panel survey
Natural Region
(NR)\a
II
District
Number of Respondents
Bindura
30
Murehwa
29
Seke
30
III
Chirumhanzu
30
Masvingo
31
Mt. Darwin
29
IV
Gokwe South
27
Insiza
23
Nkayi
25
Nyanga
30
V
Binga
23
Chipinge
29
Chivi
30
Hwange
28
Mangwe
22
Total
416
\a
Zimbabwe is divided into five agro-ecological regions also known as Natural Regions I to V. Natural Region I
and II receive the highest rainfall (at least 750 mm per annum) and are suitable for intensive farming. Natural
Region III receives moderate rainfall (650800mm per annum) and Natural Regions IV and V have fairly low
annual rainfall (450650mm per annum) and are suitable for extensive farming (Vincent and Thomas, 1960).
3. RESULTS
3.1.
Characterization of CA Households
Conservation agriculture promotions in the context of NGO support have essentially targeted
vulnerable farmers. However, these farmers are not necessarily of the same resource and
social endowments. Different household characteristics influence technology adoption
differently. Across the 15 districts, there is no significant difference in the numbers of maleand female-headed households targeted by NGOs (Table 2). This is despite the fact that
NGOs deliberately target female-headed households for relief assistance. The gender of
household head is equally shared with 49.9% being male-headed and 50.1% being femaleheaded households.
The average age of the household head is above 50 years, with the exception of Mt Darwin,
Nyanga, Chipinge and Binga where it ranges from 44 to 48 years. There does not appear to
be any significant age difference across the 15 districts. This can be attributed to the targeting
process of households by the NGOs, which includes the elderly as part of the vulnerable
households. On average, farmers have 6.4 years of formal education. This means that
household heads across the surveyed districts have attained up to primary level of education
and are generally literate. The education level has less to do with the targeting procedure of
NGOs but is vital in assessing the ability of farmers to appreciate and grasp new principles or
concepts.
In general, all the household heads have farming experience with Binga having the least with
19 years and Gokwe South the most with 38 years. This information helps to characterize the
farmers participating in conservation agriculture. These farmers have experience with their
environment and natural resources. They are thus more likely to appreciate a new technology
that has potential for better crop yields.
3
Farmers are expected to realize greater yields from conservation agriculture as they gained
experience with the technology over time. Households interviewed in the study had some
experience with conservation agriculture, with the majority of farmers having at least a
minimum of three years of practice with the technology. The most experienced farmers were
in Bindura, with more than six years of conservation agriculture practice. This is where River
of Life (RoL) pioneered conservation agriculture, with some farmers claiming to have started
in the late 1980s. Districts such as Binga, Chipinge, and Chirumhanzu had relatively less
experienced farmers, averaging less than three years because conservation agriculture
promotions by NGOs in these areas has only recently been introduced. Farmers in areas such
as Masvingo, Murehwa, and Insiza were in their fourth season of conservation agriculture
practice.
Table 2 shows that the majority of the farmers in the survey sample started practicing
conservation agriculture after being selected by NGOs. NGOs targeted farmers perceived to
be vulnerable to food production shortfalls and provided them with training on conservation
agriculture and free inputs as an incentive to try out the new technology.
In all the districts there is some evidence of chronic illness, which directly limits conservation
agriculture labor availability in the household (Table 2). On average, about 20% of the
households have chronically ill people. Seke, Bindura, and Chivi had the highest cases of
chronically ill household members. In Seke NGO targeting was based primarily on
HIV/AIDS indicators. The average household size across the survey sample is six, with fewer
contributing to full-time labor on the farm (3.7 persons per household). Binga had the largest
average household size of nine individuals. Marriage arrangements in that area are typically
polygamous (Manyena et al.,2008), resulting in larger household size.
4
Table 2. Household characteristics by agro-ecological regions and districts
Natural
region
NR II
District
Murehwa
Bindura
Seke
Average
NR III Mt Darwin
Chirumhanzu
Masvingo
Average
NR IV Nyanga
Gokwe South
Nkayi
Insiza
Average
NR V Chivi
Hwange
Mangwe
Chipinge
Binga
Average
NR II −V
Gender of household
head (%)
Male
Female
33.3
38.9
32.0
34.5
61.9
41.7
50.0
52.7
28.6
72.7
75.0
53.8
56.9
53.3
71.4
22.2
45.0
100.0
55.6
49.9
66.7
61.1
68.0
65.5
38.1
58.3
50.0
47.3
71.4
27.3
25.0
46.2
43.1
46.7
28.6
77.8
55.0
0
44.4
50.1
Mean
Mean Initially selected by NGO Presence of Mean labor
Mean
Mean
Mean age of
current
access
farming conservation for input support (%) chronically
household education
ill persons (Adult eq.) household
experience agriculture
head (years) level of
size
(%)
experience
(years)
household
Yes
No
(persons)
(years)
head (years)
59.1
59.5
56.2
58.0
47.9
50.7
58.9
52.9
46.2
55.2
61.5
53.4
53.7
53.3
52.9
53.6
47.9
44.1
50.4
53.8
6.4
4.7
6.6
6.0
6.0
7.2
6.2
6.3
7.1
6.2
7.1
6.2
6.7
7.2
5.0
6.7
6.9
6.4
6.5
6.4
37.3
34.8
31.4
34.0
26.6
26.8
34.8
29.9
23.4
38.0
36.8
23.6
30.9
28.3
25.9
22.3
24.5
19.5
24.1
29.7
5
4.1
6.0
3.4
4.4
3.6
2.8
4.3
3.7
3.9
3.2
3.3
3.8
3.5
3.7
3.4
3.9
2.8
2.6
3.3
3.7
62.5
81.8
79.4
74.7
74.2
43.8
68.3
62.5
100.0
93.1
64.0
76.9
85.2
94.7
72.7
95.7
100.0
93.1
91.2
78.4
37.5
18.2
20.6
25.3
25.8
56.3
31.7
37.5
0
6.9
36.0
23.1
14.8
5.3
27.3
4.3
0
6.9
8.8
21.6
20.7
26.7
41.4
29.5
13.8
20.0
16.1
16.7
16.7
10.7
20.0
17.4
16.0
23.3
17.9
13.6
19.4
8.7
17.2
19.9
3.6
2.9
3.3
3.3
4.1
3.5
3.5
3.7
3.1
3.3
4.6
3.3
3.6
3.8
4.1
2.8
4.0
5.2
4.0
3.7
6.3
4.7
5.8
5.6
6.1
5.8
6.0
6.0
5.4
6.3
8.3
6.4
6.6
6.7
6.2
5.5
6.5
9.0
6.8
6.3
3.2.
CA Adoption Trends
Of the 416 farmers who were interviewed in 2009, 369 (89%) dug planting basins which is
the central component of CA during the 2008/09 cropping season. This means that 11% of
the farmers did not dig planting basins. The main reason for dropping out of conservation
agriculture was the withdrawal of input support by NGOs to these particular farmers,
compounded by the general lack of inputs such as seed and fertilizer at the local markets. The
89% of farmers practicing conservation agriculture adopted various components of the
technology as shown in Table 3.
Table 3. Proportion of farmers using the following components of CF techniques (%)
Technique
a
Cropping season
2004/05a
2005/06a
2006/07
2007/08
2008/09
Winter weeding
51
87
76
71
63
Application of mulch
40
75
69
70
56
Digging of basins
100
99
99
97
89
Application of manure
89
88
89
87
80
Application of basal fertilizer
71
75
74
66
38
Application of top dressing
94
92
92
88
70
Post-planting timely weeding
94
98
99
96
85
Crop rotation
8
13
13
18
19
Data for 2004/2005 and 2005/2006 seasons was obtained during the 2006/2007 survey
3.3.
Digging Planting Basins
Most farmers are knowledgeable on when and how planting basins are dug. The digging of
planting basins is generally done using hand hoes and may require more labor in clay soils.
Though farmers with labor constraints would prefer to dig basins in sandy soils, there is a risk
of having the basin destroyed by wind (especially in Chipinge where dust storms are a
frequent phenomenon), as well as heavy rain and animals that roam freely in unfenced plots.
However, it must be noted that most farmers tend to start digging planting basins in the
months of September to October (even up to November), as a result they consider digging of
planting basins a laborious exercise yet they squeeze in the basin digging phase into a short
space of time before the onset of the rains (ZCATF, 2009).
3.4.
Weed Management
Weed pressure causes a major threat to the sustainability of conservation agriculture.
Although farmers are generally aware of the advantages of keeping the fields weed-free, there
were variations on the levels of weeding managements recommended for conservation
agriculture practices. Post-planting weeding, despite contributing to significant labor
demands, is generally practiced by conservation agriculture farmers compared to winter
weeding.
3.4.1. Post-Planting Timely Weeding
Farmers practising CA are expected to keep their plots weed free throughout the season.
Weeding should commence as soon as weeds appear. This activity is taken seriously by
farmers. Most farmers indicated that labor peaks are experienced during weeding.
Conservation agriculture plots require an average of 2−3 times weeding per season compared
to once for conventional draft tillage plots. Most farmers have an understanding that weeding
has to commence as soon as the first weeds emerge. Results from Table 3 show that 85% of
6
the respondents practiced post-planting timely weeding, and the proportion was even higher
in the earlier seasons with virtually every farmer weeding in the 2006/07 season.
There is still some confusion on when timely weeding has to end; with results showing that
28.6% of the respondents who don’t do post-planting timely weeding were not aware of the
need to keep the field weed-free even when crops had reached maturity (Table 4). As the crop
matures, farmers tend to leave the weeds in the fields as they believe crop yield will not be
compromised at this stage. During this period, farmers prioritize labor to other off-field
activities.
Table 4. Reasons for not practicing post-planting timely weeding (N=62)
Reason
Proportion of respondents
(%)
16.6
21.4
28.6
28.6
4.8
100
Land was water logged
Labor constraints
Lack of knowledge
Plot was weed free
Burnt weeds after harvest
3.4.2. Winter weeding
Winter weeding was a not a priority with 63% of the farmers practicing this activity in the
2008/09 cropping season (Table 3). Because of other off-season household commitments,
winter weeding is regarded to be of less priority. Observations made during follow-up visits
off-season to farmers’ fields were that farmers had not weeded after harvest (Table 5).
During the survey, it appeared that there was some confusion on the definition of winter
weeding and 30% of farmers did not practice winter weeding due to this lack of knowledge.
According to most farmers, winter weeding entails weeding as they dig or just before they dig
basins in September and October. Some respondents (8%) said there was no need to weed
off-season as livestock would graze whatever is growing in the fields in the winter season
whereas 4.0% of the farmers indicated that they burnt weeds after harvest as a form of weed,
pest, and disease control measure (Table 5).
Table 5. Reasons for not practicing winter weeding (N=153)
Reason
Proportion of respondents
(%)
14.0
30.0
20.0
8.0
24.0
4.0
100.0
Fewer weeds due to water logging
Lack of knowledge/yet to practice
Labor constraints
Weeds and crop residues eaten by livestock
Plot was weed free
Burnt weeds and crop residues
Total
3.5.
Mulching
Forty-four percent of the interviewed farmers did not mulch their plots during the 2008/09
cropping season. These farmers indicated that their fear was that the mulch would be
destroyed by animals and termites (17%, Table 6). There were also some farmers who tried
mulching, but discontinued since they could not really notice any immediate benefits. This is
understandable since some research in the driest areas of Zimbabwe have also indicated that
7
the obvious benefits associated with mulching may take a longer time to be realized and the
quality of the mulch is very important for soil organic matter build up. Mashingaidze et al.,
(2009) study on the contribution of mulch to yield in the short term confirm this. There are
some farmers (16%) who still did not have any knowledge about the benefit of mulch which
includes aiding in moisture retention and building up of soil organic matter in the long term
(Table 6).
In general, however, farmers seem knowledgeable about mulching although there are
misconceptions that mulching can only be done using crop residues. Generally, there is low
production of biomass in smallholder farms which may not allow farmers to meet the 30%
mulch cover as a minimum recommendation for conservation agriculture (Giller et al., 2009).
However, various other materials can also be used as mulch including leaf litter and grass.
Stone bunds may also be a viable option since they help in moisture conservation through
reduction of runoff and allow more water to infiltrate (Donovan and Casey, 1998)
There is also competition for use of crop residues which may limit its use as mulching
material. Farmers prefer to feed their crop residues, especially maize stover, to livestock. The
communal nature of the fields and grazing system in the areas means that it is difficult for
conservation agriculture farmers to control animals that wander into their plots for grazing.
This means that most of the stover is lost to animals as they graze and this issue is
exacerbated by the lack of fences in most of the fields. Legume stover (e.g., cowpea,
soyabeans and groundnuts) that may be left in the fields is quickly decomposed so that at the
start of the planting season there is little of the stover on the soil surface. .
Table 6. Reasons for not applying crop residue as mulch (N=183)
Reasons
Labor constraints
Lack of knowledge
Gave residues to livestock
Did not practice CF this season
Crop residues destroyed/given to livestock
Burnt weeds and crop residues/left weeds to dry up
Total
%
17.0
16.3
31.2
17.0
17.0
1.5
100
3.6.
Manure Application
Farmers are aware of the need to apply manure and the one-handful per basin concept to
increase fertility within the basin for the crop. Access to manure remains an issue to those
farmers without livestock. Despite having the knowledge of manure application, the study
revealed that farmers have little knowledge and limited experience on the treatment of
manure for cropping purposes. The general trend is to heap cattle dung from cattle pens. The
manure applied in the basins is usually not fully decomposed and may ‘burn’ the crop
especially if it comes in direct contact with the seed. The timing of manure application is also
another important issue that farmers tend to disregard. Farmers apply manure during planting,
which increases the labor involved during the planting phase under conservation agriculture.
Since most farmers are rushing to finish the application of manure and planting (done on the
same date), they tend to disregard the fact that the seed-manure contact may affect
germination rates. In drier areas, some farmers claimed that manure would ‘burn’ crops
particularly when the season is characterized by long dry spells. This shows that there is need
for better understanding by farmers on the right quantities that have to be applied, especially
8
in the climatically risky semi-arid regions. Some farmers also believe that manure increases
weed pressure.
3.7.
Fertilizer Application
Use of basal fertilizer in conservation agriculture plots has been on the decline since 2005/06
(from 75% of respondents using it to only 38% in 2008/09). Ninety five percent of those not
applying fertilizer in 2008/09 indicated unavailability as the reason for failing to use it (Table
7). Generally fertilizer was in short supply across the country in 2008/09 and only a few
NGOs provided fertilizer to selected recipients. There was a small proportion (2.2%) of
farmers who did not apply fertilizer to basin plots because they had used manure instead. In
some areas fertilizer was delivered late and in the case of basal fertilizer those respondents
ended up using the Compound D as topdressing. There are also issues related to fertilizer
types, with some farmers getting confused with CAN/LAN which are similar to Compound D
in color.
Table 7. Reasons for not applying fertilizer (N=258)
Reasons
Applied manure
Fertilizer not available
Lack of knowledge
Other
Total
%
2.2
94.7
0.9
2.2
100
3.8.
Crop Rotation Practices
Crop rotation is the conservation agriculture component that has hardly been adopted by
farmers across the 15 districts of Zimbabwe. Only 19% of the respondents (Table 3) practiced
crop rotation on their conservation agriculture plots in the 2008/09 cropping season. The
reasons for not practicing rotation varied with many farmers (30.6%) preferring to continue
growing the staple food plot on their most fertile plot, which is the conservation agriculture
plot. Seventeen percent claimed ignorance of the recommended practice (Table 8).
Many farmers (32.2%, Table 8) claimed that they had just started conservation agriculture
and had not yet attained the stage of rotating the fields. Other farmers said they had not been
taught how to incorporate legumes in basins as the basin spacing seemed more suitable for
cereals whereas legumes required smaller spacing and a higher plant population. Some,
however, were practicing a cereal–cereal rotation where they planted maize one year,
followed by sorghum and/or pearl millet the following year. Legume seed shortage was
another reason for not practicing rotation; the 19% (Table 3) who had practiced rotation
received seed from the supporting NGOs.
Table 8. Reasons for not practicing rotation (N=337)
Reasons
Changed plot
Yet to practice. Just started CF practice
Lack of alternative seed for rotation
Prefer cereals to legume, cereal is staple crop
Lack of knowledge
Did not practice CF this season
CF spacing not suitable for legumes
Other
Total
%
0.9
32.2
10.7
30.6
17.0
6.4
0.9
1.3
100
9
3.9.
Source of Inputs for Conservation Agriculture Plots for 2008/2009 Cropping
Season
The NGO relief programs were the main source of inputs for the 2008/09 season. (Table 9).
A large proportion of farmers also relied on maize seed from previous harvests kept in their
own stock. Most of this seed was Open Pollinated Varieties (OPV) that is usable over
multiple seasons. Market sources of seed, as expected, were limited largely due to
unfavorable market conditions that prevailed during the course of the season. Farmers relied
on own stocks saved from previous harvests for sorghum, pearl millet, groundnut and cowpea
seed. Fertilizer sources were mainly from NGO and government relief programs (about 50%).
A significant number of farmers also managed to purchase some fertilizer from retail sources
(42%).
Table 9. Source of seed and fertilizer for conservation agriculture plots
NGO
NGO previous season
Own stock
Retail shop
GMB*
Local farmer
ICRISAT
Seed fair
Total
*GMB – Grain Marketing Board
Maize
11.1
18.0
24.3
22.2
16.1
7.6
0.5
0.2
100
Sorghum Pearl millet
29.7
8.0
20.5
20.0
34.9
62.4
2.6
7.4
4.4
0
0.5
100
3.2
4
1.6
0
0.8
100
Groundnut
17.0
12.8
56.4
Cowpea
30.3
18.4
30.3
5.3
4.8
3.7
0
0
100
0.9
14.4
4.9
0.8
0
100
Fertilizer
27.5
2.9
0.6
42.2
17.3
8..5
0.4
0.6
100
3.10. Changes in Conservation Agriculture Plot Sizes
Land area allocated to conservation agriculture in some cases increased whereas it remained
the same in others due to labor constraints, or adverse field conditions such as hard soil and
infertility. Other farmers did not increase the land sizes citing shortages of seed, particularly
where an NGO originally supporting conservation agriculture had pulled out of the area.
Farmers who have been practicing conservation agriculture since 2004/05 have increased plot
sizes over the years (Figure 1). This has mostly been a response to increased yield gains,
particularly for farmers located in the high rainfall potential areas of NR II.
10
6000
Area m
2
5000
4000
3000
2000
1000
0
2004/05
2005/6
2006/07
2007/08
2008/09
Cropping Seasons
NR11
NRIII
NRIV
NRV
Figure 1. Changes in conservation agriculture plot sizes by agro-ecological regions
3.10.1. Influence of NGO Support to Conservation Agriculture Plot Size
Conservation agriculture promotions have commonly been associated with free input
packages where farmers are given seed and fertilizer for their plots. These input handouts are
usually just enough for small conservation agriculture plots. There is evidence to show that
access to inputs influences the area allocated to conservation agriculture. Farmers tend to
expand the area under conservation agriculture on the basis of input availability from NGOs.
The initial message from NGOs was to target a conservation agriculture area of 0.25 hectares
(Twomlow et al., 2008). Farmers have started to allocate closer to 0.5 hectares to
conservation agriculture (Figure 2). The capacity to acquire inputs from alternative sources
has limited the capacity for farmers to expand conservation agriculture plot sizes.
6000
5000
Access to NGO support
No access
Area under CF ( m 2 )
4000
3000
2000
1000
0
2004/05
2005/06
2006/07
2007/08
2008/09
Figure 2. Influence of NGO support on conservation agriculture plot area
11
3.10.2. Influence of Gender on Conservation Agriculture Plot Size
Evidence from the survey results indicate that male-headed households take up conservation
agriculture technology at a larger scale than female-headed households (Figure 3). Femaleheaded households are more likely to face a bigger land constraint. Figure 3 shows that maleheaded households have a larger conservation agriculture plot area than their female
counterparts except for the first 2004/05 season where the conservation agriculture area was
similar for both male- and female-headed households. This is largely because it was the first
season for most farmers and they tended to stick to smaller plot sizes regardless of land
availability.
7000
Male-Headed
6000
Female-Headed
2
Area under CF (m )
5000
4000
3000
2000
1000
0
2004/05
2005/06
2006/07
2007/08
2008/0
Figure 3. Influence of gender on conservation agriculture plot area
3.10.3. Influence of Labor Access on Conservation Agriculture Plot Sizes
Conservation agriculture is a labor-intensive technology and farmers have generally cited
labor availability as one of the main constraints to increasing plot sizes. Figure 4 shows that
farmers with more labor available are more likely to expand their area over time. If a
household has two adults at most, the expansion of conservation agriculture plot size is
limited compared to a household with more than two adults.
6000
At most 2 Adults
More than 2 Adults
2
Area under CF (m )
5000
4000
3000
2000
1000
0
2004/05
2005/06
2006/07
2007/08
Figure 4. Influence of labor access on conservation agriculture plot size
12
2008/09
Conservation agriculture plots are ideally supposed to be maintained for a number of seasons,
allowing the basins to accumulate fertility. Farmers are expected to maintain the same
planting stations and plots, which in theory should reduce the labor required in subsequent
seasons. However, this poses challenges in rotations due to differences in cereal and legume
spacing. Also, maintaining the same basins becomes difficult if they are no longer visible in
the next season. Farmers are sometimes forced to change plots due to safety concerns from
livestock or to look for more fertile land. Table 10 highlights reasons for changing
conservation agriculture plots and planting stations.
Table 10. Reasons for changes in conservation agriculture plot and basin station
Why change CF plot?
Looking for a more fertile plot
Instructed by NGO staff
Plot infested by termites
To enable rotation
Plot was far from homestead
Plot prone to water logging
Plot unprotected from livestock
Did not practice CF
%
25.8
6.7
1.5
26.3
1.5
3.6
2.1
32.5
Why change basin station
Instructed by NGO
To change basin size
Different spacing after rotation
CF plot changed
Basins no longer visible
Spreading fertility across CF plot
Did not practice CF
%
1.1
9.3
20.9
28.5
16.9
5.6
17.7
Total
100
Total
100
3.11. Production Impacts
In general, yields from conservation agriculture plots are higher than those from conventional
draft tillage plots (Table 11). Maize, which is the main crop grown in all the districts, yielded
on average 1546kg/ha on conservation agriculture and 970kg/ha on conventional draft tillage
plots in the 2008/2009 cropping season. This can be attributed to the efficiency of the
technology in providing good results across the four natural regions surveyed.
Table 11. Maize yields from conservation agriculture (CA) plots and non CA plots for 3
cropping seasons
Natural Region
District
NR II
Bindura
Murehwa
Seke
NR III
NR IV
NR V
2006/2007
CA
Non- CA
1950
920
_
_
2008/2009
CA
Non- CA
1109
510
1490
1208
2266-
897
2132
1412
1635
962
-
Chirumhanzu
1162
789
1207
340
1428
914
Masvingo
1735
725
3060
557
2439
1355
Mt Darwin
1105
701
1011
368
1190
877
Gokwe South
2056
421
766
285
1433
713
Insiza
-
-
800
247
1646
1105
Nkayi
1244
789
1175
398
1579
792
Nyanga
1917
1250
1247
787
1308
874
Binga
-
-
500
250
1384
868
Chipinge
-
-
222
79
1262
1105
Chivi
1500
910
1061
270
1658
874
Hwange
1464
385
561
424
1563
713
614
283
1048
792
1114
407
1546
970
Mangwe
Total Average Yield
2007/2008
CA
Non-CA
1570
765
Larger yield gains are realized in conservation agriculture than conventional draft tillage plots
because the technology promotes improved management and targeted application of
13
fertilizers, timeliness of operations like planting, frequent weed control, and timely fertilizer
application. There is potential for even greater yield responses given a favorable rainfall
season.
While the season had normal to above-normal rainfall in the survey districts, the planted area
is not enough to meet household food requirements to next harvest for most districts. Figure 5
shows the contribution of conservation agriculture to household food security. Assuming that
an average household of six people requires 900kg of cereal in a year and does not have cash
to access the market to buy grain, only farmers in Murehwa, Mt Darwin, Gokwe South,
Masvingo, Chivi, Nkayi, Hwange, Chipinge, and Binga are likely to meet food security
requirements till the next season. The proportional contribution of conservation agriculture to
total cereal grain production was more than 50% only in Bindura, Masvingo, and Seke. The
rest of the areas indicate more production on conventional draft tillage plots.
2500
Non-CA
2000
Total Cereal production ( kg)
CA
1500
1000
500
0
Nyanga
Murehw a
Bindura
Mt Darwin Gokw e South
Chirumhanzu Masvingo
Chivi
Nkayi
Hwange
I nsiza
Mangwe
Chipinge
Binga
Seke
Figure 5. Contribution of CA to household food security (total cereal production in kg)
4. RECOMMENDATIONS FOR IMPROVING CONSERVATION AGRICULTURE
TECHNOLOGY TRANSFER
The promotion of conservation agriculture technology has thus far been characterized by a
mix of positive experiences and some apparent challenges. It therefore becomes critical to
strategize on the best ways to address the challenges and sustain efforts of enhancing the
potential benefits that have been realized this far. The following section is a discussion of
some issues that have arisen in the transfer of conservation agriculture and strategies to
address those:
14
4.1.
Targeting farmers for conservation agriculture promotion
The promotion of conservation agriculture has primarily targeted vulnerable households as a
way of mitigating the effects of food insecurity and chronic poverty. There is some concern
however, about the extent to which these vulnerable groups can maximize input and
technology support. In some instances, vulnerable farmers face severe labor constraints and
chronic illnesses. This limits productivity particularly due to high labor demands associated
with digging basins and timely weeding. Targeting has often excluded better resource
endowed farmers, who could be better positioned to maximize on conservation agriculture
practices. As a result, such farmers have, in most cases, not been exposed to training on
conservation agriculture principles, yet they traditionally drive crop production and other
related enterprises that provide livelihood means to the resource-constrained community
members. Such exclusion has limited the technology transfer to diverse resource groups
within the communities. It is therefore important to include both resource endowed and
vulnerable households in the promotion of CA.
4.2.
Level of NGO Support
Since 2004 NGOs within the context of conservation agriculture have spearheaded
humanitarian efforts to address the lack of input access and low food production by providing
seed and fertilizer to help farmers re-establish their farming operations. As a result, farmers
tend to associate conservation agriculture adoption with access to free inputs. Farmers are
therefore prone to stop practicing conservation agriculture when input support is withdrawn.
Sustained conservation agriculture promotions should move away from NGO-related input
support and encourage market-led interventions such as input credit facilities through seed
and fertilizer companies and other public institutions, such as the Grain Marketing Board.
4.3.
Weeding Practices
Farmers can derive considerable yield benefits from increased weeding frequency. The fact
that farmers failed to practice winter weeding due to poor understanding of its importance
and low prioritization due to other labor commitments calls for increased training. Off-season
conservation agriculture activities such as winter weeding have been implemented with some
difficulty. There has also been limited emphasis in training on the appropriate time to start
winter weeding and farmers often do so just before digging the basins in August/September.
Winter weeding is also a challenge because of conflicting demands for off-season labor.
Farmers tend to concentrate on their gardens and other off-farm activities and are less willing
to continue to weed their conservation agriculture plots. It is also socially uncommon and
perceived strange to continue tending to the rainfed fields during the off-season; hence,
farmers are reluctant to do so as a way of avoiding embarrassment.
Future conservation agriculture scaling out initiatives should consider the introduction of
herbicides where appropriate to reduce labor requirements associated with weeding.
Encouraging the use of cover crops and other mulch sources can also assist in weed
suppression.
4.4.
Mulching in Conservation Agriculture
The importance of mulching does not seem apparent to farmers. Close to half of the
interviewed farmers did not apply mulch in the 2008/09 cropping season. Some farmers have
also tended to limit mulching to the application of crop residues. There is competition
between the use of crop residues as mulch and for livestock feed. Communal grazing laws
commonly demand the use of crop residues as livestock feed, making it difficult for
conservation agriculture farmers to reserve residues for mulching purposes. Plots are usually
15
unfenced and grazing cattle enter during the off-season period. As a way of addressing this
conflict there are instances where some farmers have removed the residues from their fields
to store them in a safe place usually at their homes and put them back on after digging basins.
While this provides a practical and feasible option in unfenced fields, it defeats the concept of
permanent soil cover provision of conservation agriculture and increases labor for farmers.
Mulching has not shown any immediate benefits to crop productivity, largely because of the
limited quantity of mulch (less than the 3t/ha optimum level). Mashingaidze et al.,(2009) in a
two season study report no yield benefits from mulching. As such farmers are still skeptical
about the benefits of continued application of crop residues as mulch. Availability of mulch
remains a challenge owing to low biomass production, particularly in the drier Natural
Regions IV and V (Giller et al. 2009) and therefore this requirement could be inappropriate
given farmers’ agro-ecological resource base. Future trainings should emphasize alternative
ground cover methods that could be more accessible to the farmer such as grass and leaves.
4.5.
Fertilizer Use
Inorganic fertilizer has consistently proved to be an important factor in yield improvement,
even in low rainfall areas. Farmers applying fertilizer at an appropriate time will significantly
improve their yield even in drier areas. Availability and accessibility of fertilizer however,
remains a challenge and farmers largely depend on the NGO input packs and government
subsidies. Farmers usually substitute basal fertilizer with organic fertilizers such as manure
and compost when fertilizer is unavailable. Top dressing is still critical because of lack of
substitute organic soil amendments.
Farmers’ perceptions on fertilizer use are shifting and many farmers now appreciate the
benefits of using fertilizer. There is need to improve fertilizer access through markets and
credit facilities to ensure continued use of fertilizer among smallholder farmers. Alternative
soil amendments such as termitaria, compost and manure should also be promoted. Farmers
should be trained on treatment and preparation of these alternative soil fertility amendments
to ensure they obtain maximum benefits from their use
4.6.
Labor Demands
Labor demand has been a limiting factor in the expansion for conservation agriculture area.
This labor constraint becomes even more adverse if targeted households have limited labor
due to HIV/AIDS, chronic illness, or are child headed. NGO targeting criteria has often
focused on such households for conservation agriculture promotions, leading to
overwhelming labor demands.
Some labor demanding components such as weeding can be reduced through introduction of
herbicides. While the study is assessing labor requirements in conservation agriculture, care
should be taken to consider not only the labor requirements but, in addition, labor
productivity since increased labor input also translates to increased production. Thus, any
comparisons between conservation agriculture and conventional draft tillage benefits should
focus on labor productivity i.e. the returns per unit labor invested.
4.7.
Mechanization of Conservation Agriculture
Future conservation agriculture promotions should explore innovative ways that address the
high labor requirements associated with the technology. There is need for mechanizing some
of the operations such as basin preparation and weed control. The use of jab planters that are
also labor saving can be alternatives for vulnerable farmers (Bishop-Sambrook et al.2004). On
16
the other hand, for resource endowed farmers, the use of rippers and direct seeding equipment
could be good options particularly if the linkages to both input and output markets are
secured for improved profitability.
4.8.
Institutional Support
Extension provides an important link between the technology and farmers and ultimately
sustains conservation agriculture adoption. However, this role has so far been limited due to
resource constraints in the national extension service. It is important to strengthen the role of
AGRITEX to implement and promote improved cropping technologies to farmers. NGO
promotions of conservation agriculture are not permanent; therefore, this practice can only be
sustained through involvement of the national extension service. Institutionalization of the
technology promotions through AGRITEX will significantly contribute to sustained
conservation agriculture adoption.
Current economic development efforts in Zimbabwe to open up markets will likely lead to
improvements in the function of the commercial sector, including rural agro-dealers. Linking
farmers to input markets such as commercial agro-dealers and distributing relief inputs
through local retail outlets is likely to play an important role in sustained CF gains. This will
include the use of vouchers to purchase seed and fertilizers that have generally been
distributed freely to vulnerable farmers. Government plays a vital role in creating a favorable
policy environment that will ensure the possibility of continued CF promotion and adoption.
The role of policy support should ideally be able to create: accessible input markets,
strengthened extension support to farmers, link farmers to credit facilities, and create output
markets.
5. CONCLUSION
This panel study provides indications that there are some benefits to CA across different
agro-ecological regions. Most farmers are now experienced in CA, having had at least three
years of practicing the technology. Notable benefits include timely planting and better
moisture conservation leading to increased yields. The most significant and sensitive yield
factors in CA included good management as reflected in plot size, weeding frequency, and
application of top dressing fertilizer. There are however some aspects of the CA technology
that farmers are still finding difficult to fully practice. In most instances, winter weeding is
not being done at the recommended time, which is soon after harvesting up until planting
time. This is because of the labor constraint and competition for other off-season activities.
Mulching is also done to a limited extent as farmers do not seem to see its immediate
benefits, and also because of crop residue shortages and conflicting uses as livestock feed.
There is need to promote other mulching materials that could be more readily available for
use as ground cover. Crop rotation is still very limited due to legume seed shortage and
farmer priorities towards cereal staple food crops.
Fertilizer use has consistently shown to have high payoffs to yield improvement but its use is
limited by unavailability and unaffordability to farmers. Farmers have generally attained
good yields on CA plots, with an average CA yield of 1.5 tons per ha compared to 1.0 tons
per ha under the conventional farmer practice. CF practice has however been closely
influenced by NGO support. Farmers who fail to get input support often stop practicing CF.
Only in three of the 15 survey districts did CF production contribute to more than 50% of
17
household food security requirements. This limited contribution is due to small area size for
CF plots which limits total production. High CF labor demands and input shortages often
force farmers to operate on small plots. Extension support has thus far been led by NGOdriven programs. The national extension service has had limited activity in transferring the
CF technology to farmers, largely due to operational challenges in AGRITEX in the face of
economic challenges that were prevailing in the country. There is still need for improvements
in CF technology transfer strategies, incorporating research and extension, and favorable
policies to ensure sustained CF uptake.
18
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