VERTICAL GARDENING FOR VEGETABLES

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Vertical Gardening for Vegetables
S.N.H. Utami, Darmanto and R. Jayadi
Gadjah Mada University
Yogyakarta
Indonesia
Keywords: vertical gardening, vegetables, chinese cabbage (Brassica rapa var.
parachinensis L.)
Abstract
With the over-population of the world ever increasing and water and land
being finite resources, alternative options are being sought for food production,
whilst minimizing land use. Vertical gardening is a method of growing plants in an
upright form by making use of stakes, cages, bamboo and other vertical supports.
The purpose of an intensively grown garden is to harvest the most produce possible
from a given space.
An experiment about vertical garden was done at the Centre for Land
Resources, Gadjah Mada University, Yogyakarta, Indonesia. Raised beds (shelf, a
place holder) or growing beds are the basic unit of an intensive garden. Several of
these beds were made with 6 levels of 6×4 m2 and 4 levels of 4×1.72 m2. Nutrients
were supplied by organic matter (manure and compost), while water was supplied as
treated wastewater. Then several vegetables (chinese cabbage, lettuce, water
spinach, chili red) and fruits (lemon, guava, mango, passion fruit) were planted.
The results showed that vertical gardening is best suited for plants that
require maximum sunlight such as fruit and also several vegetables. Plants grown in
a vertical garden are less accessible to diseases and pests, and crop harvesting and
cultivation is easier. Vertical gardening provides adequate aeration to the plants,
and also increases the beauty of the garden. Overall, the yield of vertical gardening
is higher than traditional plantation methods. For example, we found yields of
chinese cabbage of 45 t ha-1, while the average production in the field is 10-25 t ha-1.
INTRODUCTION
The space needs for the human activities in urban areas and the issue of global
climate change have become a problem in the sustainability of environment, particularly
water conservation and green open space. These issues need immediate action particularly
in countries where population growth is rapid. As one of the developing countries with an
expected population in 2011 close to 260 million people, Indonesia is facing similar
problems due to the increase of population density which is not balanced with the
availability of land, green open space and clean water. The emerging Indonesian middle
class and a high level of urbanization have triggered a rapidly growing property sector in
major cities like Jakarta, Surabaya, Bandung, Yogyakarta, Bali, Medan and Makassar
putting pressure on the space needed, as well as on water supply and sanitation services.
Urban areas in Indonesia need comprehensive solutions to control those issues without
neglecting the sustainability of the ecosystem and environment where they live. Green
roofs and vertical gardens seem to be the answer for the serious problems. Vertical
gardening is an ideal option for those staying in city areas, where agricultural land is
limited (Nitisapto, 1993; Damastuti, 1996; Binabid, 2010). Farming systems with a very
limited land availability can also take advantage of land-saving agricultural technology.
Vertical gardening/farming systems are not only suitable for small farms, but can also be
developed on marginal lands, because plants grown in growth media do not depend on the
state of the local area (Nitisapto, 1993). Vertical farming systems can also be applied to
multilevel buildings, public housing or even on settlements in areas that do not have any
pages. With this method we can utilize the land optimally and more efficiently.
Furthermore, it is said that a vertical farming system is able to double crop yields up to
Proc. First IS on Sustainable Vegetable Production
in South East Asia
Eds.: S. De Neve et al.
Acta Hort. 958
,
ISHS 2012

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3-4 fold when compared with conventional systems, i.e., directly planted in the ground
(Widarto, 1994; Sutarminingsih, 2003).
The objectives of this works were to determine yield from several vegetables
grown in a vertical garden system whilst reducing the wastewater that is being disposed to
the environment.
MATERIAL AND METHODS
This experiment was conducted at the roof garden of the Centre for Land
Resources, Gadjah Mada University, Yogyakarta, Indonesia. This building has a domestic
wastewater treatment plant system and a solar cell system. Domestic wastewater is
pumped to the top of the building using solar energy. Two units of slow-sand filter which
are installed on the top of building are operated to filter the wastewater. The wastewater
was used as irrigation water. The water quality parameters were analyzed, including pH,
Suspended Solid (SS), Electrical Conductivity (EC), Chemical Oxygen Demand (COD),
Biological Oxygen Demand (BOD), Fe, and Mn.
Several beds (shelfs, a place holding) were made: 6 levels of 4 m2, 4 levels of
1.72 m2, one PVC collumn of 2 m high (Figs. 1-3). Soil (Entisols) was amended with
water and nutrients to give favorable conditions for plant growth. Nutrients were supplied
by organic matter (30 t ha-1 manure and 10 t ha-1 compost, mixed with soils before
planting), while water was supplied as treated wastewater. Then several vegetables
(chinese cabbage, lettuce, water spinach, red chilli) and fruits (lemon, guava, mango and
passion fruit) were planted. Before planting, soils, compost and manure were analysed.
All vegetables were harvested at the age of maximum vegetative stage. The roots and
leaves were separated, weighed fresh and dry weights were recorded. On this green
building several vegetables and fruit were planted, but here we focus mainly on the
chinese cabbage crops.
RESULTS AND DISCUSSION
The purpose of intensive vertical gardening is to harvest the most produce possible
from a given space. An intensive garden minimizes wasted space. The practice of
intensive gardening is not just for those with limited garden space; rather, an intensive
garden concentrates efforts to create an ideal plant environment, giving better yields. A
vertical vegetable garden is easy to plan and build.
Wastewater Treatment Quality
Table 1 shows the mean quality of wastewater after treatment. The water pH was
about 7.5-7.7. The wastewater recycling installation increased wastewater quality through
slow sand filter. Slow sand filter significantly decreased Suspended Solid (SS), Chemical
Oxygen Demand (COD), Biological Oxygen Demand (BOD), Fe and also Mn. All
parameters of water quality were eligible for irrigation water according to FAO standards
(Ayers and Westcot, 1994).
Vegetables Production
Total biomass of Chinese cabbage was harvested at 28 days and separated into
shoots and roots. There were no significant differences in fresh and dry biomass weight
among the levels of raise beds. The fresh and dry biomass of Chinese cabbage of the top
raised bed (1st) till the lowest bed (6th) are almost the same, but the data showed that the
top and the lowest tends to have lower weight. Biomass production is primarily driven by
photosynthesis, while photosynthesis to a great extent depends on light interception,
which furthermore varies with leaf area of the canopy (Dorais, 2003). Chinese cabbage is
adapted to cool temperature (16-20°C) and moist climates (Wichmann, 2002), so it
prefers not too much sunlight. The second till fifth raised beds gave cool and moist
climate, but the top raised bed was hotter than the other raised beds, while in the lowest
raised bed there was a lack of sunlight.

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Soil Quality after Vertical Gardening
Many interrelated factors influence soil productivity (Havlin et al., 2005), but soil
organic matter content is the most critical, because of its influence on many biological,
chemical, and physical characteristics inherent in a productive soil. The steady-state
organic matter level depends on soil and crop management practice influencing C
accumulation and loss. Table 5 shows that the soil quality after vertical gardening
increased drastically. The greatest source of soil organic matter is the residue contributed
by crops, but also from the manure addition. Tables 2 and 3 show the quality of compost
and manure which were added to the soil. The compost and manure contain relatively low
concentrations of N, P, and K. They typically decompose slowly and behave as a slow-
release source of N over many months or years since the rapidly decomposable
compounds have been previously degraded during the composting process.
The soil quality after compost and manure application was better, especially for
the pH, cation exchange capacity, organic matter content and total N. The soil reaction
(pH) has a direct and indirect nutritional effect on plant growth. In the range of 6.0 to 7.0,
nearly all nutrients are available in optimal amounts. The C:N ratio of the organic
material added to the soil influences the rate of decomposition of organic matter and this
results in the release (mineralisation) or immobilization of soil nitrogen. The key to
building healthy soil is organic matter management. Building up and maintaining soil
organic matter contributes to nutrient management through better soil tilth and thus root
exploration, enhanced biological activity which increases mineralization and nutrient
availability, and greater cation exchange capacity which enhances nutrient retention. Soil
organic matter also promotes an abundance of microorganisms that can stimulate root
growth and help solubilize nutrients.
The biomass productivity of vegetables expressed in g/plant by vertical gardening
was still below the average yield in the field, especially for water spinach, leek, cabbage,
nevertheless by vertical gardening we have a lot of plants so the productivity of
vegetables (t/ha) were always higher than the productivity in the field. The problem is the
quantity of the soil as crops medium and also the sunlight. Cabbage as cruciferous
vegetables grow well without much sunlight. If there is a lot of sunlight, then they will
not grow well. Lettuce and water spinach are green leaves vegetables. The only difference
between the leaves grown in full sunlight or in the shade is in the thickness of the leaf.
Leafy vegetables that grow in the shade are slightly thinner but have the same taste.
Based on the research, only the small trunked vegetables were able to grow equally as
vegetables grown in the field, such as water spinach and lettuce.
The result showed that one of the major advantages of vertical gardening is
harvesting maximum products in a minimum space. Following are some of the benefits of
vertical gardening: 1) some of the highly spreading plants can be grown effectively in a
vertical garden; 2) plants grown in a vertical garden are less accessible to diseases and
pests; 3) easy access to ripe vegetables; hence crop harvesting or cultivation is easier; 4)
vertical gardening provides adequate aeration to the plants; and 5) vertical gardening
increases the beauty of the garden. Nitisapto (1993) reported water saving by vertical
gardening with 1 column (Fig. 3) was three times because water was only used for
transpiration and little for evaporation.
CONCLUSION
The purpose of intensive vertical gardening is to harvest the most produce possible
from a given space. An intensive garden minimizes wasted space. The practice of
intensive gardening is not just for those with limited garden space; rather, an intensive
garden concentrates efforts to create an ideal plant environment, giving better yields. A
vertical vegetable garden is easy to plan and build. Vertical gardening for vegetables
provides many benefits including: save space, easy to harvest, better air circulation, keeps
vegetables off the ground and better yields.

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ACKNOWLEDGEMENT
Thanks to Ministry of National Education, Republic Indonesia (Directorate of
Research and Service for the Community) for financial support.
Literature Cited
Ayers, R.S. and Westcot, D.W. 1994. Water quality for agriculture. FAO Irrigation and
Drainage Paper. Rome.
Binabid, J. 2010. Vertical garden.The study of vertical gardens and their benefits for low-
rise building in moderate and hot climate. A Thesis Presented to the Faculty of the
USC School of Architecture University Of Southern California.
Blanc, P. 2008. The Vertical Garden in Nature and the City. New York: W.W. Norton.
Damastuti, A. 1996. Vertical agriculture system. Wacana No. 3/Juli-Agustus 1996. (in
Indonesian).
Dorais, M. 2003. The use of supplemental lighting for vegetable crop production: light
intensity, crop response, nutrition, crop management, cultural practices. Canadian
Greenhouse Conferences, 9 October 2003.
Havlin, J.L., Tisdale, S.L., Beaton, J.D. and Nelson, W.L. 2005. Soil Fertility and
Fertilizers. An Introduction to Nutrient Management. Seventh edition. Pearson
Prentice Hall, Upper Saddle River, New Jersey.
Nitisapto, M. 1993. Vegetables cropping with Vertical Agriculture. Faculty of
Agriculture, Universitas Gadja Mada Yogyakarta. (in Indonesian).
Sutarminingsih, L. 2003. Pola Bertanam Secara Vertikal. Kanisius. Yogyakarta.
Wichmann, W. 1992. World Fertilizer use manual. IFA. Paris, France.
Widarto, L. 1994. Bercocok Tanam Secara Bertingkat (Vertikultur). Penebar Swadaya.
Jakarta.
Tables
Table 1. Quality of wastewater before and after treatments.
Parameter Before treatment After treatment
pH 7.50 7.56
Electrical conductivity (µS cm-1) 300 302
Ferrum (Fe) (mg L-1) 21.06 0.24
COD (mg L-1) 12.58 1.32
Suspended solid (SS) (mg L-1) 418 0.08
BOD (mg L-1) 9.79 0.78
Mangaan (Mn) (mg L-1) 5.91 0.025
Tabel 2. Quality of compost.
Parameter Value
moisture (%) 25
pH H2O 7.18
C (%) 26.64
Organic matter (%) 45.93
Total N (%) 1.44
Total P (%) 2.37
Total K(%) 1.39
C/N 18.50

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Table 3. The quality of manure.
Parameter Value
Water content (%) 8.2
pH H2O 7.92
EC (mS cm-1) 41.3
Organic C (%) 45.15
Total N (%) 1.22
Total P (%) 0.37
Total K (%) 3.12
CEC cmol(+)kg-1 51.07
Table 4. Fresh and dry biomass weight of Chinese cabbage.
Number of seedbed Fresh biomass weight (g) Dry biomass weight (g)
I 185.66a 18.15a
II 240.12a 21.09a
III 302.64a 20.55a
IV 194.5a 24.31a
V 184.4a 14.52a
VI 178a 24.89a
Numbers in each column by common letters are not significantly at 5% Duncan’s multiple range test.
Table 5. Soil quality after vertical gardening.
Number of
seedbed pH Organic C
(%)
Total N
(%) C/N Cation exchange capacity
(cmol(+)kg-1)
Control* 6.50 0.69 0.06 11.33 7.87
I 7.30 4.43 0.33 13.2 13.48
II 7.32 3.77 0.33 11.42 13.71
III 7.65 3.61 0.28 12.89 14.37
IV 7.22 3.78 0.27 14.0 13.54
V 7.43 3.78 0.31 12.78 15.18
VI 7.23 3.77 0.32 11.78 15.80
* the soil (Entisols) before treated with manure and compost.

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Table 6. The yield of vegetables by vertical gardening.
Vegetables
Mean
weight
(g/plant)
Mean
weight
(kg/4 m2)
Weight
(kg/ha)
Yield
(t ha-1)
Average yield
(t ha-1 in
the field)
Ratio yield
by vertical gardening/
in the field
Water spinach
(Ipomoea aquatica) 40.62 3.65 9139.5 9.13 6.65 1.37
Leek
(Allium ampeloprasum var. porrum (L.)) 143.25 8.595 21487.5 21.48 10.51 2.04
Chinese cabbage
(Brassica oleracea L.) 309.6 18.57 46440 46.44 19.97 2.32
Lettuce
(Lactuca sativa) 131.26 3.15 7876 7.87 9.62 0.81
Chilli red
(Capsicum annuum) 916.5 3.66 9165 9.16 11.3 0.81
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Figures
Fig. 1. Six levels of shelf (raise beds), size 6×4 m2 for chinese cabbage.
Fig. 2. Vertical gardening by four levels of shelf (raise beds), size 4×1.72 m2 for lettuce.

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Fig. 3. Vertical gardening with one column 2 m for eggplants.