THE EFFECT OF AVAILIBLE SOIL ON THE HEALTH AND PHYSIOLOGY OF THE
SPINACIA OLERACEA PLANT (title should be THE EFFECT OF SOIL AVAILIBILTY ON
THE HEALTH AND PHYSIOLGY OF THE SPINACIA OLERACEA PLANT – just a
suggestion)
Abdul Aziz, Nash Robertson *Name should be put together with school information, no spaces*
Department of Biological Sciences, Saddleback College,
Mission Viejo, California CA 92692. (school address should not be italicized, look at correct
formating)
Growing plants in a non-traditional setting has seen a rise in popularity. Due to lack
of gardening space in urban settings, individuals are increasingly using techniques more
akin to potting. With the hope of determining how an herb or vegetable, such as Spinacia
olercea or the common spinach can be optimally grown in a potting environment with
limited soil resources, the investigators will attempt to judge how the spinach plant will
develop in pots, varying in sizes. (hypothesis clearly stated, but talk about growing plants to
eat)Spinach seeds were purchased on 11 October 2011 from the Mission Viejo, California
Home Depot. The 6-Gram Bloomsdale long standing spinach seeds are from the Martha
Stewart Living Company; the seeds are USDA approved to be organic. The seeds were then
taken to Saddleback College located in Mission Viejo, California. The greenhouse annex of
the Math and Science building would be utilized as the site for planting and development.
Observations were noted consistently on Monday, Wednesday, and Friday of each week,
whilst on the 36th day after initial planting, the Spinacia oleracea were uprooted and health
markers (Explain what health markers are) were measured. Final results and analysis
indicate that there is no significant difference among the health markers of mass (p =
0.654), number of leaves (p = 0.663), (and) root depth (p = 0.819). However, the findings
suggest a significant difference in diameter of the Spinacia oleracea stalk (p = 0.021) (talk
about what statistical analysis you did to get these numbers, did you use anova with
Bonferoni correction, two tailed t-test, etc). Appropriated soil volumes appear to neither
hinder nor benefit plant health.
Introduction
Harvesting fruits and vegetables in non-traditional urban settings has become
commonplace, due in part to green initiatives as well as economic benefits, which befall it. Lack
of gardening space in urban settings has compelled individuals to increasingly use techniques,
which are more akin to potting. It is estimated that urban dwellers may spend anywhere between
40%-60% of their income on groceries and other various foodstuffs (Wakefield, 2007).
Especially in turbulent economic times there is no surprise many communities have seen an
exponential rise in urban-gardening. Cities such as Detroit, Chicago, Toronto, and Los Angeles
to name a few have incorporated community gardens within residential areas in order to expedite
this growing trend. Urban-gardening can be observed and discussed through various methods, as
a socio-cultural event and implication on community, but also through a biological and botanical
lens. Gardening for ones own consumption promotes individuals to cultivate the healthiest
produce. Through this reasoning lies the pursuit of attempting to create optimum circumstances
for plant health and physiology. Dr. Coley discusses the significance of resource and soil
availability in regards to plant growth ascertaining that when resource(resources) are limited,
plants’ leaf lifetime, is affected (1985).
Spinacia oleracea or the common spinach plant is a familiar staple in the inventory of
urban-gardens; and as the plant is consumed, its benefits begin to take hold. Spinacia oleracea
has been found to be nutrient rich, containing essential vitamins including K, A, C, and E, while
also proving rich in anti-oxidants. Whereas the nutritional contributions of the plant sway the
urban-gardener in the plants favor, reasons for planting spinach does not stop here. On account
of the Spinacia plants’ accessibility in regards to temperature range, which is from 5-20 degrees
Celsius, it allows spinach to have a diverse temporal schedule for planting and growth (Boese,
1990). The researchers have decided to observe the implication of various soil amounts within
pots of Spinacia oleracea. Four health markers (what are health markers? What did the
researchers decide what to use as health markers?) have been chosen to help to ascertain the
wellness of the plant. The researchers hypothesize that the markers of physiological health will
be significant amongst the Spinacia oleracea having plentiful soil. (hypothesis stated)
 Hypothesis stated
 Spinach background described
 Reason to do research stated
Materials and Methods
Spinacia oleracea seeds were purchased from Home Depot in Mission Viejo, California
on 11 October 2011. The ‘Bloomsdale’ long standing spinach seeds were collected and packaged
by the Martha Stewart Living Company; the seeds are USDA approved to be organic. The study
was performed at the greenhouse annex of the Math and Science building located at Saddleback
College in Mission Viejo, California. The greenhouse setting provided minimal changes in
temperature (25 - 35C) while protecting the plants from potentially lethal pests. Saddleback
College donated “Pro-mix BX with Mycorise” potting soil manufactured by Premier Horticulture
inc. and 30 pots, (semi colon) ten pots of three different sizes, (take out comma)to the
researchers for growing and housing the Spinacia. All measurements of mass were calculated by
a top loading balance provided by the Saddleback College Biology department.
Research started on 11 October 2011 by filling the different pots with a measured mass of
soil. The ten small pots contained a volume of approximately 175 cm3 and were filled with 85 g
of soil. The ten medium pots contained a volume of approximately 300 cm3 and were filled with
175 g of soil. The ten largest pots contained a volume of approximately 550 cm3 and were filled
with 360 g of soil. All 30 pots were positioned on a table adjacent to the greenhouse window, to
maximize sunlight exposure, and remained stationary for the duration of the research. One seed
was allocated to each container and planted at a soil depth of 3 cm. Once the sowing was
complete, the researchers observed the volume of water needed in order to saturate the soil in
each of the pot sizes. The smallest pots received 25 mL of water, the middle pots received 50 mL
of water, and the large pots received 75 mL of water. Subsequent watering of the Spinacia
utilized the calculated water volume and took place at a consistent time every Monday,
Wednesday, and Friday. As the plants matured and sprouted leaves the researchers added a
“misting” of the spinach leaves with water filled spray bottle to the maintenance routine.
The Spinacia was allowed to grow for five weeks before the plants were “uprooted” to
determine the physiologic health of each individual plant. Uprooting the plants consisted of
emptying all (of) the soil from the pot and running the spinach under light water to wash the soil
away from the root structures. After the washing, all the plants were air dried for 30 minutes
before quantitative measurements were processed. The major factors considered for the
physiological health of the Spinacia were the mass, the number of leaves, size of edible leaves,
and root diameter. All the data was entered into Microsoft Excel and a statistical analysis was
performed on each of the aforementioned metrics to determine if there was a statistical difference
between soil volumes.
Results
The mean mass of spinach plants in the 175 cm3 pot was 0.192 g  0.071, the mean mass
of spinach plants in the 300 cm3 was 0.144 g  0.041, (and) the mean mass of spinach plants in
the 550 cm3 was 0.296 g  0.186. The statistical analysis on the average mass of the spinach
plants indicated that soil volume had no significant difference according to results of an ANOVA
(p > 0.05) and a Bonferroni correction (p > 0.05).
Figure 1. The mean masses of the spinach plants indicated no significant difference (p = 0.654,
ANOVA, n = 10) dependent on three variant soil volumes. The statistical insignificance in the
difference of the three average masses was confirmed by a Post Hoc Bonferroni correction.
Error bars are mean  SEM.
The mean number of leaves on each of spinach plants in the 175 cm3 pot was 5.0  1.2,
the mean number of leaves on each of spinach plants in the 300 cm3 was 5.4  0.76, (and) the
mean number of leaves on each of spinach plants in the 550 cm3 was 6.2  0.76. The statistical
analysis on the average number of leaves on each of the spinach plants indicated that soil volume
had no significant difference according to results of an ANOVA (p > 0.05) and a Bonferroni
correction (p > 0.05).
Figure 2. The mean number of leaves on the spinach plants indicated no significant difference (p
= 0.663, ANOVA, n = 10) dependent on three variant soil volumes. The statistical insignificance
in the difference of the three average masses was confirmed by a Post Hoc Bonferroni
correction. Error bars are mean  SEM.
The mean root depth of spinach plants in the 175 cm3 pot was 4.0 cm  1.0, the mean root
depth of spinach plants in the 300 cm3 was 4.4 cm  0.9, (and) the mean root depth of spinach
plants in the 550 cm3 was 4.8  0.46. The statistical analysis on the average root depth of the
spinach plants indicated that soil volume had no significant difference according to results of an
ANOVA (p > 0.05) and a Bonferroni correction (p > 0.05).
Figure 3. The mean root depths of the spinach plants indicated no significant difference (p =
0.819, ANOVA, n = 10) dependent on three variant soil volumes. The statistical insignificance in
the difference of the three average masses was confirmed by a Post Hoc Bonferroni correction.
Error bars are mean  SEM.
The mean stalk diameter of spinach plants in the 175 cm3 pot was 0.6 mm  0.16, the
mean stalk diameter of spinach plants in the 300 cm3 was 0.9 mm  0.20, (and) the mean stalk
diameter of spinach plants in the 550 cm3 was 1.2  0.11. The statistical analysis on the average
stalk diameter of the spinach plants indicated that soil volume provided a significant difference
(p = 0.021) according to results of an ANOVA. Furthermore, a Post Hoc Bonferroni correction
supported the significant indication, specifically illustrating the variance between the smallest
175 cm3 pot and the largest 550 cm3 pot.
Figure 4. The mean stalk diameter of the spinach plants indicated a significant difference (p =
0.021, ANOVA, n = 10) dependent on three variant soil volumes. A Post Hoc Bonferroni
correction confirmed the statistical significance between the smallest and largest soil volumes.
Error bars are mean  SEM.
The only statistically significant result from this trial was observed in the comparison of
the average diameter of spinach plant stalk between the containers with the smallest and largest
soil volumes.
Discussion
The first indicator of plant health chosen for this experiment was mass of dried plant. On
a previous study of growth kinetics on spinach plants it has been observed that dried plant mass
was an indicator of overall health (Boese, 1990). The results of this trial indicate no significance
between pot sizes and dried (plant) mass, as can be seen in figure 1. Contrary to researcher
expectations the smallest volume plants outweighed the plants with the 300 cm3 of soil.
Although the plants in the mediums sized pots were the smallest by mass, the plants provided the
researchers interesting data. The medium sized potted plants began to flower, and while plants in
the other varied sizes also flowered, the 300 cm3-potted plants were the most numerous
flowerers. This may be a result of the greenhouse ambient temperature averaging 28 degrees
Celsius over the duration of the experiment. The preferred temperatures for optimal spinach
growth as noted by Dr. Boese, is in fact between 5, and 16 degrees Celsius (1990).
The second health marker studied by the researchers focused on the quantity of leaves
sprouted per individual plant. Analysis of leaf quantity has been used previously as a
nondestructive way in which to measure plant health (Wood, 2000). The researchers noticed a
trend regarding greater soil content resulting in more leaves as seen in figure 2. However the
ANOVA showed not(no) statistical difference in leaf number.
Root depth was the third health marker observed by the researchers, measuring the length
of the longest root. The decision to include this factor as a health marker was influenced by
previous studies, correlating root restriction to plant health. One such study found that root
restriction resulted in depressing production in both root and shoot for cucumber plants
(Kharkina, 1999). The researchers found that this metric(that the length) had the least variance
among the differing soil volumes, as indicated in figure 3.
Stalk diameter was the last health marker chosen by the researchers, who were able to
locate numerous studies regarding stalk diameter. Wider stalks can support taller and weightier
plants, indicating superior health. One such study found a relation between stalk diameter and
height of maize (Earley, et al, 1965). As can be noted in figure 4 stalk diameter measurements
showed a significant difference between the three potted sizes, in which the largest potted plants
provided the widest diameter stalks. (explain why there might be a difference in root diameter
between the three pot sizes, and add some literature explaining this)
While statistical analysis does not show any significant difference, the researchers have
observed the viability of spinach plants grown in smaller volume pots. These observations
contradict what has been previously stated in articles regarding proper soil volumes for spinach.
The implications for viable produce grown with less soil are immense, especially in urbangardening communities, for which space is limited and must be used sparingly.
Given the opportunity, the researchers would pursue the study of soil amounts and plant
health by continuing to push the boundaries of soil necessity, attempting to observe how little
soil volume can be implemented until a significant difference is ascertained. The researchers
would eventually attempt to calculate and analyze the nutrient content between the spinach
plants grown in various soil amounts, again hoping to achieve an optimally healthy spinach plant
using the least amount of soil volume.
Acknowledgments
The authors would like to thank Professor Steve Teh, Julie Anderson, Tom Burrows, and
Saddleback College for access to the campus greenhouse and for providing the pots and soil
needed to complete the valuable research.
Literature Cited
Blair, Dorothy, Giesecke, Carol, Sherman, Sandra, A dietary, social and economic evaluation of
the Philadelphia Urban Gardening Project, Journal of Nutrition Education 23(4): 161-167. 1991
Boese SR, Huner NPA. Effects of growth temperature and temperature shifts on spinach leaf
morphology and photosynthesis. Plant Physiol. 1990;94:1830–1836.
Coley, Phyllis, and Bryant, John, Resource Availability and Plant Antiherbivore Defense
Science 22 November 1985: Vol. 230 no. 4728 pp. 895-899
Early, E.B., Miller, R.J., Reichert, R.H., Hageman, R.G., Self, R.D. (1965) Effect of Shade on
Maize Production Under Field Conditions. Crop Science. 6:1, 1-7
Kharkina, T. G., Ottosen, C.-O. and Rosenqvist, E. (1999), Effects of root restriction on the
growth and physiology of cucumber plants. Physiologia Plantarum, 105: 434–441.
K. D. M. McConnaughay and F. A. Bazzaz Is Physical space a soil Resource?
Ecology Vol. 72, No. 1 (Feb., 1991), pp. 94-103
Sinclair, Thomas, Ray, Jeffery
The effect of pot size on growth and transpiration of maize and soybean during water deficit
stress J. Exp. Bot. (1998) 49(325): 1381-1386 doi:10.1093/jxb/49.325.1381
Wakefield, Sarah Fiona Yeudall, Carolin Taron, Jennifer Reynolds, and Ana Skinner
Growing urban health: Community gardening in South-East Toronto Health Promot. Int. (2007)
22(2): 92-101 first published online February 26, 2007
Wood, Andrew and Roper, James, A Simple & Nondestructive Technique for Measuring Plant
Growth & Development
The American Biology Teacher Vol. 62, No. 3 (Mar., 2000), pp. 215-217
Review Form
Department of Biological Sciences
Saddleback College, Mission Viejo, CA 92692
Author (s): Abdul Aziz and Nash Robertson
Title: The Effect Of Available Soil On The Health And Physiology Of The Spinacia Oleracea
Plant
Summary
Summarize the paper succinctly and dispassionately. Do not criticize here, just show that you understood the paper.
In these days, people living in cities are starting to grow plants to eat in pots due limit amount of
soil space. The researchers want to know if the amount of soil availability has any effect on the
plant health. The plant was grown in three different pot sizes. The small pot size was 175 cm3 ,
the medium pot size was 300 cm3, and the large pot size with 550 cm3. The plant health was
measured quantitatively by observing 4 health markers which is the mass, amount of leafs, root
length, and root diameter of the plant. The results showed that there is no statistical significance
in the plant mass, amount of leafs, and root length using ANOVA and Bonferroni correction in
the three different pot sizes. The only statistical significance shown was the root diameter using
ANOVA between the three different pot sizes. Using Bonferroni correction, there was significant
root diameter size between the small and large pot size. In conclusion, from this experiment, the
researchers discovered that the amount of soil availability did not affect plant health, therefore
people living in cities can grow their plants to eat in pots, instead of the common way of growing
plants to eat in field gardens.
General Comments
Generally explain the paper’s strengths and weaknesses and whether they are serious, or important to our current
state of knowledge.
The strengths
Material and methods were explained in details. Statistical analysis were done correctly using
ANOVA and Bonferroni correction to see observe for any differences between the plant health in
the three different pot sizes. Information about the spinach background was explained clearly and
the reason for doing this experiment was explained clearly. The graphs were easily
understandable and captions are clear. Figures are cited correctly in the article, made the reader
easily look back and forth at the graph for reference. Not a lot of grammatical issues. Uses
correct subject verb agreement and uses correct spelling.
The weaknesses
Abstract needs correct formatting. Talk about the importance of growing your own food to eat
with limited amount of soil availability. Talk about what statistical analysis that you used to get
your results.
Introduction needs more explanation about health markers.
Discussion needs more work. In the discussion, talk about why there is a significance in plant
root diameter between the three different pot sizes and add cited sources to explain this
significance. Explain difference in plant root diameter could be due to soil type, more room for
root diameter to expand, possibly due to amount of water given, and etc.
Discuss why there is no significance between the plant mass, amount of plant leafs, and length of
plant root and add cited resources to explain.
Overall
Paper is good and understandable. Paper needs more explanation in the discussion and in the
abstract. This research is important and useful for the readers and to the science community.
Originally, before reading this research paper, I thought that plants need a certain amount of soil
to grow and that the more space and soil a plant has, the bigger and healthier it will grow. After
reading this article, everything that I thought of before has been changed. Now I realize that you
can grow spinach in small amount of soil and it will be healthy and edible. For other plant
growers, this research article would motivate urban growers to continue to grow their plants to
eat in just regular pot size and other urban growers to be not discouraged to grow plants to eat
due to lack of soil area. This article has encouraged me to want to start growing plants to eat in
just regular pots.
Technical Criticism
Review technical issues, organization and clarity. Provide a table of typographical errors, grammatical errors, and
minor textual problems. It's not the reviewer's job to copy Edit the paper, mark the manuscript.
This paper was a final version
here) (This is a rought draft)
This paper was a rough draft (check mark
Observe all the corrections made in the article. Little amount of grammatical errors discovered
and typographical erros discovered.
Recommendation
 This paper should be published as is
 This paper should be published with revision
 This paper should not be published