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The 2011 AGGRAND Vegetable Productivity Study is part of an ongoing study of crop growth, crop yield and soil analysis over multiple growing seasons. In the second year of this work, soil nutrient levels and yield trends are clearer as a result of following sustainable growing techniques in the AGGRAND plot. This year’s program featured yield comparisons between a plot fertilized with AGGRAND fertilizers and soil amendments, a plot fertilized with a leading organic fertilizer, and an unfertilized control plot. The organic fertilizer manufacturer’s recommendations were followed. Water only was added to the control plot at the same time the organic fertilizer was applied to the experimental plots. Four common garden vegetables - tomatoes, potatoes, broccoli and carrots - were grown and compared for size, weight, total number and total weight. The AGGRAND fertilizer program, as in 2010, produced greater yields when compared to the plot fertilized with a leading organic fertilizer.
Plots fertilized with AGGRAND natural fertilizers outperformed the plots fertilized with the leading organic fertilizer and the control plots where no fertilizer, only water, was applied.
The report summarizing the results of the 2010 AGGRAND Growth Study (AMSOIL, 2011) provided a brief history of some of the researchers and proponents of organic/agriculture such as Dr. William Albrecht, J.I. Rodale, Aldo Leopold, Rudolf Steiner and Sir Albert Howard. During the past 30 years, organic farming techniques have developed as agricultural research discovered that agricultural fields are living systems with each component dependent on many variables within the environment. Environmental factors to consider include weather, soil type, soil chemistry, soil biology, past and current agricultural methods, and use of pesticides and herbicides. Researchers such as J.W Doran, Neal Kinsey, Jeff Moyer, and others, have brought a systems - or eco-agriculture - approach to an otherwise chemical-based agricultural system that is underpinned by short-term increase in yields. Numerous papers, books and publications provide important documentation of the organic/sustainable agriculture community as a viable force in the industry. The concepts presented by these researchers are incorporated in this study, along with crop growth and fertilizer recommendations by AGGRAND.
- Doran recognized the need for traditional evaluation of soil nutrient levels as well as a systematic approach that includes evaluation of soil condition, including assessment of the soil’s physical, chemical and biological properties and processes. (Liebig, 1999)
- Moyer conducts his own research at the Rodale Institute, where he has been employed for more than 28 years. Moyer’s approach to organic agriculture includes planting cover crops to provide weed control and organic matter to build the soil and allow soil biology to provide power to the system. Limited tillage of the cover crop meets the fertility needs of the system. Crop rotations reduce disease and infestations by insects. (Moyer, 2011)
- Kinsey adopts the concept of providing a sustainable system from a slightly different approach. Using soil analysis as the main driver to maintain soil fertility in traditional and organic growing situations, Kinsey recognizes the value of alternative, organic-based fertilizers and soil amendments but stipulates the soil must have mineral and organic matter balance before soil and crop improvements are noticeable. (Kinsey, 2009)
AGGRAND natural fertilizers and soil amendments are formulated with natural materials such as emulsified fish, kelp, lime, fulvic and humic acids, sulfate of potash and others. These materials are recognized as part of a sustainable cropping system designed to build the soil by enhancing microbial growth and provide the necessary nutrients for plants to grow and thrive. (Albrecht, 1996, Kinsey, 2009, National Stone Association, 1986, Senn, 1987). The competitive organic fertilizer used in this study is formulated to deliver similar benefits but appears to be less highly formulated than AGGRAND products. The following fertilizers and amendments were employed in this study:
- Organic hydrolyzed fish seaweed-based product (2-3-1) commonly used by organic growers and the consumer market.
The objective of this research was to determine yield results, weight and maximum length or diameter of garden vegetables fertilized with the AGGRAND program in accordance with the AGGRAND Gardening Guide (AMSOIL, 2010) compared to similar plots fertilized with a leading organic fertilizer following the manufacturer’s mix ratios and application protocols. In addition, soil evaluations were continually executed to determine nutrient shifts for each system and the impact of each fertilization system.
Weather data collection is essential to document environmental conditions the plants encounter throughout their growth and development, and for comparison of the growing conditions historically found in the geographic area.
To aid in the collection of weather data, AGGRAND installed a weather station at the end of the 2010 growing season. Data was collected as early as October 2010. The components include instrumentation for data collection, display and storage. All components are sold by Davis Instruments of Hayward, Calif. and include the Solar-Powered Vantage Pro2 station (Part #6152) equipped with rain collector, anemometer, temperature and humidity sensors and a fan-aspirated radiation shield (Part #7747) to reduce temperature and humidity variations. (Figure 1)The data from the Vantage Pro2 station is transmitted to a Vantage Pro2 Console for viewing (Part #6312) (Figure 2) via two transmitters, solar (Part #7627) and AC powered (Part #7626). Weather information received at the console is transmitted to a PC (Figure 3) with WeatherLink (Part #6510) and Agricultural/Turf management software (Part #6511). This software provides instant weather observations at the garden plots and archives data every hour.
Figure 1: Weather data collection station
Figure 2: Data display console
Figure 3: PC data display
In April 2011, temperature (Part # 6470) and Watermark® moisture (Part # 6440) sensors were installed in the middle of the plots at a depth of 12 inches (30.5 cm) to monitor soil conditions. These sensors connect to a solar transmitter (Part # 6345) that transmits data to the console and PC. (Figure 4)
Each planter was tilled to a depth of approximately 8 inches. Soil samples were taken. Using a soil sampling probe, samples were obtained from the top 6 inches of the planting bed at nine evenly spaced points in each quadrant.
See Figure 5.
Figure 4: Measuring sensor depth and installation of sensors
Figure 5: Soil sampling plan
Figure 6 shows the relative position of each growth plot, the intended fertilization regimen and soil sample identification.
Soil samples were analyzed at Midwest Laboratories, Omaha, Neb., and evaluated for percent organic matter, available phosphorus (weak and strong Bray), exchangeable potassium, hydrogen, magnesium and calcium, pH, buffer index, cation exchange capacity (CEC), percent base saturation of cation elements and carryover nitrogen as nitrate. Micronutrient analysis of sulfur, manganese, boron, zinc, iron and copper, and evaluation of excess lime and soluble salts also was conducted. (See Graphs 7 -10 in the Results section for a summary of all soil analyses obtained during this study.)
Carbon dioxide respiration is an indicator of soil health. It is a measure of the bacterial action within the soil that leads to mineralization of key soil nutrients such as nitrogen and phosphorus. (Haney, 2008) Use of the Solvita Soil Respiration Kit from Woods End Research of Mount Vernon, Maine is accepted by the U.S. Department of Agriculture. (United States Department of Agriculture, 1999, Haney, 2008)
The Solvita respiration system includes a Solvita Digital Color Reader, test jars and color-metric paddles (Part # DCR-soil). Soil samples from each plot quadrant were evaluated for CO2 respiration by weighing 105.00 grams of soil into a glass jar using an AND FX3000i digital balance. (Serial #: 15610355) The respiration indicator paddles (Serial #: 238210S, Expiration: 08/26/2011) were placed into the jar and sealed. (See Figure 7) Four samples for each growth plot were prepared. After 24 hours of incubation, the paddles were removed and placed in the Solvita color reader to determine the amount of CO2 respired. (See Figure 8) The paddles were again inserted into the jar, sealed and read again at 96 hours. See Graph 6 for data summary below.
Figure 7: Test jars, soil and paddles
Figure 8: Solvita color reader with paddle inserted
A growth plot sowing plan was established to use the area most efficiently while providing ample room for the vegetables to grow and develop, leaving enough room to water, fertilize and weed the plots. A two-foot walking path was established between the vegetable types. See figure 9. To reduce wind, and maintain plot air and soil temperatures, a six-foot wide windscreen was attached to the existing fence around the perimeter of the site. SunBlocker Premium, 60 percent shade cloth was obtained from Farm-Tek Supplies, Dyersville, Iowa, (Part #103764).
Figure 9: Growth plot planting plan
The vegetables chosen in this study are popular hybrid varieties that produce good yields in cooler climates. Their seeds were established in Minnesota or Wisconsin. The following seeds and seed potatoes were planted in this study:
Minnesota Certified Seed Potatoes
From Dan’s Feed Bin, Superior, Wis.
Variety: Nelson Hybrid, 0157J
From Jung Seed, Co. of Randolph, Wis.
Variety: Packman Hybrid, 01430A
From Jung Seed, Co. of Randolph, Wis.
Variety: Celebrity Hybrid VFFNTASt, 00175A
From Jung Seed, Co. of Randolph, Wis.
Celebrity® plants from Dan’s Feed Bin of Superior, Wis.
Plants were approximately 8 inches to 10 inches in height.
On April 25, 2011 two tomato seeds were sown per pot in two flats of 3.5 inch x 3.5 inch pots filled with Pro-Mix (PGX) Professional Potting Soil Part # 0463 from Quakertown, Penn., for a total of 72 seeds. The plan was to thin to one plant per pot, (36 plants) and select the best 27 plants to be placed outdoors. Seeds were planted approximately 0.25 inches under the surface of the soil. Each flat received 3000 mL of water measured with a 2000 mL measuring pitcher. Water was absorbed into the planting medium by capillary action until moist. Flats were placed into the newly constructed growth table and illuminated by fluorescent growth lamps, with growth mats providing heat. To maintain soil moisture and heat, a plastic drape was placed over each flat. The same procedure was used for the broccoli seeds, with five flats, for a target of 90 plants after thinning to one plant per pot for a total of 72 of the best plants to be placed outdoors. See Figure 10. Figure 10: Newly-seeded tomato and broccoli flats
Heat Mats: (2) 20.75 inches wide x 48 inches long from Hydrofarm®, Petaluma, CA,
Growth lamps configuration alternating, per side:
Four: Sylvania 40W GRO-LUX F40 GRO
Four: VitaLite® 40W duroLite® Light duration: 14 hours per day
Soil Temperature, 1 inch (2.54 cm) beneath surface = 33.1°C (91.5°F) as measured by a Cooper digital thermometer (model # DFP450W).
Initial lamp height above table: 7 inches (17.8 cm)
Temperature and soil moisture checked daily
Monitoring of soil temperature and moisture found soil temperatures from 90°F to 100°F (32.2°C to 37.8°C) on April 27. While there was concern the temperature was too high for proper germination of the tomato and broccoli seeds, on April 28 plants in 28 broccoli pots sprouted. The plastic covers were removed from all broccoli flats. The height of the growth light was increased to 9 inches (22.9 cm) and 1000 mL of water was added using a 1000 mL pouring pitcher to each tomato and broccoli flat. The relative dryness of each flat necessitated addition of 1000 mL of water to each flat on April 29. On May 2, tomatoes in four pots had germinated and 44 broccoli pots had germinated. The soil temperature ranged from 75°F to 89°F (23.9°C to 31.7°C) Lamp height was adjusted to 6 inches (15.2 cm) above the table. On May 5, 2000 mL of water was added to each flat. On May 6, another 1000 mL of water was added to each flat, while lamp height was increased to 7 inches (17.78 cm) above the table. At this time, 14 tomato pots and 46 broccoli pots had germinated.
After the weekend of May 7 and 8, tomato germination held steady at 14 pots. A probe found a lack of seed germination. Pots were replanted with 24 seeds and watered with 2000 mL in each tomato flat. Germinated tomato plants (14) were consolidated into one flat. Soil moisture was monitored and, on May 10, 3000 mL of water was added to each broccoli flat and the germinating broccoli plants were consolidated into separate flats. Plants showed increased vigor as a result of the additional watering. The heat lamp was terminated for the broccoli plants but maintained on the tomato plants. Tomato plants and seeds were given 3000 mL water on May 13.
On May 16, the germinated broccoli and tomatoes were segregated into three divisions: AGGRAND, Control and Leading Organic as follows:
Broccoli (Soil Temperature: 68°F to 72°F (20.0°C to 22.2°C) Fertilized each plot with 25 mL of water/fertilizer mixture applied with a 25 mL graduated cylinder. See Figure 11.
AGGRAND – 28 plants (5 mL measured with 10 mL graduated cylinder, NOF 4-3-3 Lot: 879-053 in 1000 mL distilled water measured with a 1000 mL graduated cylinder)
Control – 29 plants (25 mL of distilled water added)
Leading Organic – 29 plants (2 mL of the leading organic fertilizer measured with 10 mL graduated cylinder in 1000 mL distilled water measured with a 1000 mL graduated cyclinder)
Tomatoes: Fertilizer each plot with 25 mL of water/fertilizer mixture, applied with a 25 mL graduated cyclinder. See Figure 12.
AGGRAND – 8 plants (5 mL measured with 10 mL graduated cylinder, NOF 4-3-3 Lot: 879-053 in 1000 mL distilled water measured with a 1000 mL graduated cylinder)
Control – 5 plants (25 mL of distilled water added)
Leading Organic – 8 plants (2 mL of the leading organic fertilizer measured with 10 mL graduated cylinder in 1000 mL distilled water measured with a 1000 mL graduated cylinder)
Figure 11: Fertilizing broccoli seedlings
Figure 12: Fertilizing tomato seedlings
Segregated tomato plant flats were watered with 1000 mL of water on May 19. On May 20, 10 of the 18 replanted tomato pots exhibited germination. On May 23, 2000 mL of water was added to the tomato seed flat and 3000 mL of water was applied to the broccoli start flats. On May 24, the lamp height above the tomato plants was increased to 10 inches (25.4 cm). Another 200 mL of water was added to each established tomato plant pot using a graduated cylinder. Each tomato plant received 100 mL of water and each broccoli flat received 1000 mL of water. The tomato seedling flat received 1000 mL of water. The lamp height was increased to 14 inches (35.6 cm) above the table for tomatoes and 13.5 inches (34.3 cm) above the table for the broccoli plants on May 27. Hardening — preparation for outdoor planting — for tomatoes and broccoli included placing them in the AGGRAND laboratory’s entrance breezeway for about four hours a day from May 25 to May 27. On May 31, following the four hours of placement in the breezeway, the hardening process for these plants increased to include placement outdoors in direct sun for an hour and a half at a temperature of 76°F (24.4°C). Soil dryness was observed. Three AGGRAND broccoli plants and two broccoli plants fertilized with the leading organic product were watered with 100 mL of water using a graduated cylinder. The plants were then transferred to the breezeway.
On June 1, 12 Celebrity tomato plants were purchased from Dan’s Feed Bin of Superior, Wis. to supplement the tomatoes grown from seed. The target number of tomato plants per plot was nine with five plants raised from seed and four from Dan’s Feed Bin. On June 2, the broccoli and tomatoes were planted, fertilized or watered according to the 2011 Fertilization Plan. Tomatoes were fertilized or watered (Control plants) with a volume of 1000 mL measured with a 1000 mL graduated cylinder per the Fertilization Plan. The broccoli plants received fertilizer/water by applying 6000 mL of fertilizer mix or plain water, applied with a watering can per row. See Tables 1 and 3, scroll down to view.
Figure 13: Planting tomato seedlings
Figure 14: Fertilizing tomato plant w/AGGRAND
Figure 15: Planting broccoli seedlings
Figure 16: Watering control broccoli plants
In preparation for potato planting, on May 5, Kennebec seed potatoes were cut into pieces to isolate two eyes. In order to have an adequate number of eyes for good sprouting, 26 seed potatoes were cut into 80 pieces. The potato pieces were stored in a cool, dry, dark area, and the cut surface was allowed to dry until planting. On May 11, the potato pieces were planted in the northeast quadrant of each growing plot, 8 inches (20.3 cm) deep and covered with 3 inches (7.6 cm) of soil. Each plant was fertilized or watered with a volume of 1000 mL measured with a 1000 mL graduated cylinder per the Fertilization Plan. See Figures 17-18 below Tables 1 and 3, pages 11-13. On June 1, potato plants in all growth plots had emerged.
Figure 17: Planting potatoes
Figure 18: Fertilizing AGGRAND potatoes
Carrot seed is very small and difficult to plant evenly. On June 2, the carrot seed was weighed (7.32 grams) and divided by the number of total rows to be planted (24) to determine the weight of seed planted per row (0.61 grams). After the plants were established, they were thinned according to the Planting Detail Plan. See Tables 1 and 2.
Figure 19: Sowing carrot seed
Figure 20: Fertilizing carrots, organic fertilizer
Table 1: Planting detail
After all plants and seeds were established, weeding, cultivating and watering were monitored and are summarized in Table 2. Weather observations are summarized in the Results and Discussion section of this page, scroll down.
Table 3 summarizes fertilizer applications and mix ratios for each plot; 6000 mL of fertilizer mix or water was applied with a watering can per row on all plants after initial planting and fertilizer application. The application date is shown in red. Control applications, containing only tap water, followed the same timing and volume as the leading organic fertilizer applications. The leading organic fertilizer was applied at regular two-week intervals after the initial planting and establishment of the plants. Tables 4, 5 and 6 summarize the fertilizer formulations that were employed on the growth plots.
Table 3: Fertilizer application timing and formulations
* Recommendations per Gardening Guide and Cabbage study.
NOF: Natural Organic Fertilizer
NBM: Natural Bonemeal
NKP: Natural Kelp & Sulfate of Potash
NLL: Natural Liquid Lime
Table 4: AGGRAND fertilizer application timing and formulations
Table 5: Leading organic fertilizer application timing and formulations
Table 6: Control plot fertilizer application timing and formulations
Soil samples were obtained on Sept. 26, when the harvest was nearly completed and before tilling all of the planters. Soil samples, 6 inches deep from nine evenly spaced points, were obtained, mixed and forwarded to Midwest Laboratories for analysis that included percent organic matter; available phosphorus (weak and strong Bray); exchangeable potassium, hydrogen, magnesium and calcium; pH; buffer index; cation exchange capacity (CEC); percent base saturation of cation elements; carryover nitrogen as nitrate; micronutrient analysis of sulfur, manganese, boron, zinc, iron and copper; and evaluation of excess lime and soluble salts. (See sampling plan in Figure 21) Three post-harvest samples were tested and all soil samples are summarized in Graphs 7 to 10, on pages 36 and 37.
Figure 21: Post-harvest soil sampling plan
On Oct. 10, the remaining vegetation was mulched into the soil to maintain acceptable organic material and nutrient levels. Composted manure (0.05-0.05-0.05) (American Countryside: Infinity Fertilizers, Milan, Ill.) also was incorporated into the soil, with twenty, 30-pound (13.6 kg) bags, five bags in each growth quadrant. The compost was raked to evenly disperse on the surface and then tilled to a depth of approximately 8 inches. The soil temperature and moisture probes were reset.
Figure 22: Compost on soil surface
Figure 23: Tilling in vegetation and compost
As reported in the 2010 Vegetable Productivity Study (G2851, AMSOIL, 2011), crop vigor was determined by measuring the plants’ height, reproductive stage and leaf color. Like crops in the other growth plots were examined in the same way and the results were compared. To provide objective data, a Field Scout CM1000 Chlorophyll Meter was obtained from Spectrum Laboratories of Plainfield, Ill. (Part # 2950, Serial # 539). The CM1000 was generated from technology developed by NASA starting in the 1990s. During this period and into the 21st century, NASA launched a number of satellites that measured the Earth’s natural processes. One of the parameters evaluated by these Earth Observing Systems satellites was the density, health and distribution of the Earth’s vegetation. In order to make plant health measurable, scientists at the NASA Stennis Space Center invented a device that measures the amount of light absorbed and reflected by the Earth’s vegetation. The ratio of the percentage of reflectance at the differing wavelengths of light provides a relative number that correlates to the amount of chlorophyll in the plant’s leaves. (NASA, 2011) Chlorophyll levels are an indicator of the amount of nitrogen in plants and are directly related to plants’ vigor and — in cases of plant stress — nitrogen needed for optimal growth. (Murdock, et.al. 2004) This technology, developed by Spectrum as a handheld device, effectively monitors the growth of cotton, corn, wheat, turf grasses and many other crops. (Carson, 2004) Factors such as chlorophyll levels, leaf texture and the amount of pubescence of each leaf species account for data variability.
On June 24, levels of chlorophyll were measured in the broccoli and potato plants. On August 22, tomato plants and carrots were tested for relative chlorophyll levels. The readings were taken in full sun, between the hours of 10 a.m. and 2 p.m. for optimal intensity. See Figure 24. Table 11 Figure 22: Compost on soil surface. Figure 23: Tilling in vegetation and compost.
Figure 24: CM1000 measuring a potato plant
Protective sleeve Absorbing and reflected beam
The focus of this study was to determine total yield by weight and number of tomatoes from each plot, but other parameters, such as plant vigor and appearance, are helpful in developing the history of why plants under certain fertilization programs yield more fruit than others.
Tomato plants were started from seed, but only 18 plants emerged out of 72 seeds sown. This is a 25 percent success rate. The low germination rate could be attributed to the high temperatures of the heating mats causing a high rate of evaporation for low moisture levels and rapid accumulation of residual salts in close proximity to the seed. As a result, four additional plants were purchased for each plot. The number of plant starts was reduced to nine to provide more spacing for ease of harvest, less fruit on the ground and better air movement through the plot.
The tomato plants encountered slow initial growth because of unseasonably cold temperatures throughout the month of June. Cut worms also were a problem and six plants were replaced after damage from this pest. Small sleeves were cut from sample bottles to protect the plant when the main stem was at the most succulent stage in its development. See Figures 25 and 26.
Figure 25: Protective sleeve
Figure 26: Tomato plant with protective sleeve
Tomato growth rate rapidly increased during July because of warmer temperatures. Tomato support cages were installed on July 5, and plot comparison pictures were taken from late June through the month of August. Figure 27 shows the comparison between fertilizer programs.
Figure 27: Tomato Plants, July 13
On July 13, most of the AGGRAND-fertilized tomato plants were blooming. A lesser number of the Leading Organic plants were in bloom and only a few of the Control plants were blooming. To determine plant vigor, chlorophyll readings were taken of the tomato plants in each plot on July 20. Five plants on the south and west sides of each plot were evaluated with the aim of obtaining the best sun angle for maximum light intensity. Eighteen data points were taken at random for the AGGRAND and Leading Organic plants with 17 readings obtained for the Control plot. See Table 7.
Table 7: Relative chlorophyll readings - tomato plants
The data shows the AGGRAND-fertilized plants had more measurable chlorophyll, and, hence, more nitrogen in the leaves correlating to increased vigor. This also substantiates observations that the plants subjected to the AGGRAND fertilization program yielded larger plants, earlier; more blooms; and earlier, more prolific fruiting when compared to the other growth plots.
Tomato plants were photographed on August 22 and documented exceptional growth in AGGRAND plots and the bottom leaf die-back on the Leading Organic and Control plants. See Figure 28.
Figure 28: Tomato plants, August 22
The lower leaves in all plots began turning brown. The moisture levels in AGGRAND, Control and Leading Organic plots being 79, 30 and 54 centibars, respectively. On Aug. 29, tomato plants in all plots were watered by spraying the leaves and allowing the water to wet the entire soil layer. The flow rate of the watering system was determined to be 3.33 gallons/minute. After 15 minutes of watering, the total volume added to each 9-foot by 9-foot tomato plot was approximately 50 gallons.
On September 13, the tomato harvest commenced according to established criteria as follows:
Tomatoes to be orange to red on the vine
Fruit on the ground counted and measured, even when green
All fruit, even if it is green, harvested when a freeze is imminent
Determine the weight and maximum diameter for each tomato per plot
Figure 29: Tomatoes at various ripening stages
Each tomato was weighed using an AND FX3000i digital balance, serial number: 15610355, (figure 30) and the maximum diameter was measured with a Mitutoyo Corporation Digimatic Caliper, Model CD-6 CSX, Serial number: 07435188. The diameter was measured perpendicular to the axis of the stem and center core of the fruit. (figure 31)
Figure 30: Weighing procedure
Figure 31: Measuring maximum diameter
Tomatoes were harvested on Sept. 13, 15, 16, 19, 20, 22, 23, 26, 28 and 30, as well as Oct. 3 and 5 when all remaining tomatoes on all plots were picked. Table 8 summarizes the harvest results.
Tomatoes fertilized with the AGGRAND fertiliztion system produced heavier fruit in greater numbers for more total weight when compared to plants that were fertilized with the Leading Organic product. As expected, the Control plants fared the worst as far as quantity and total weight.
Broccoli is considered a cooler-climate vegetable and was expected to grow well in Superior. With 85 plants emerging out of the 180 seeds planted, the germination rate was 47.2 percent. This low success rate was most likely caused by the high temperature of the plant starter heating mats. In the first few days after planting — when the plants are most vulnerable — cut worms severed one plant in the Control plot and three plants in the Leading Organic plot. The four damaged broccoli plants were replaced and fertilized with 1000 mL of the appropriate mixture based on the initial planting formulations. Fortunately, there were excess broccoli starts to curb some of the cut worm damage. On June 8, two broccoli plants in the AGGRAND plot were nipped off by worms. They were replaced and fertilized using 1000 mL of AGGRAND planting mixture. One Control broccoli plant and one Leading Organic broccoli plant was nipped off by cut worms on June 15. They were replaced and the Leading Organic plants were fertilized, while the appropriate amount of water was applied to the Control plants.
In the effort to control cut worms, plastic vials with the top and bottom cut off were slipped around the base of the plants and stuck into the soil on June 16. (See Figures 25 and 26) On June 20, the final cut worm casualty was observed. The plant was replaced and fertilized. Plant totals for each plot were 24 in the AGGRAND plot, 23 in the Leading Organic plot and 22 in the Control plot.
On June 24 plant vigor was determined by measuring chlorophyll levels of the broccoli plants. Each plant was scanned, and the data was downloaded into a spreadsheet. The data was averaged and standard deviation was determined to arrive at the final, relative chlorophyll reading. See Table 9.
Table 9: Relative chlorophyll readings - broccoli plants
The data above shows the AGGRAND-fertilized plants had more measurable chlorophyll, and, hence, more nitrogen in the leaves translating to increased vigor. This also substantiates the observations that the plants subjected to the AGGRAND fertilization program yielded larger plants, earlier, with more blooms, for earlier and more prolific fruiting when compared to the other growth plots. Images obtained of broccoli plants on June 29 revealed exceptional growth in the AGGRAND plants when compared to the Leading Organic and Control plants. See Figure 32.
Figure 32: Broccoli plant comparison, June 29
On July 13, heads were forming on 20 of 24 broccoli plants in the AGGRAND plot. The Leading Organic plot had heads forming on 12 of 23 plants, and the Control plot had heads on three of 22 plants.
Figure 33: Broccoli plant comparison, July 13
Harvest of AGGRAND broccoli commenced on July 20. Superior development of plants fertilized with AGGRAND was observed in comparison to the Leading Organic and Control plots. The broccoli stems were cut so the entire length of harvested head was 4 inches (10.2 cm) long. Each broccoli head was weighed using an AND FX3000i digital balance, serial #: 15610355 and the head maximum diameter was measured with a Mitutoyo Corporation Digimatic Caliper, Model: CD-6” CSX, Serial #: 07435188.
See Figure 34.
The broccoli harvest occurred over the following days: July 20, 22, 25; Aug. 1, 4, 8, 12, 16, 19, 22, 26, 29 and September 1, 6 and 9. Many of the broccoli plants continued to produce after September 9, but the vegetables exhibited stem toughness and the propensity to flower very quickly.
Figure 35: AGGRAND broccoli harvest on August 22
The AGGRAND fertilization system broccoli plot produced heavier heads and higher per-plant quantities than the produce grown with the Leading Organic fertilizer. As expected, the Control plants fared the worst as far as quantity, total weight and the number of cuttings per plant.
Carrots are a popular, easy-to-grow garden vegetable that provide excellent food value. Because of the loose soil in the planting beds, all plots provided an excellent yield. The carrots were sown in each plot on June 2, with the rate of seeding exceeding the target number of plants expected per row. To provide proper spacing, plant density was projected to be 27 carrots per row.
The seed took approximately one month to germinate, which is longer than anticipated and the result of cold June temperatures. The carrots were not affected by the cut worms that caused problems in the broccoli and tomato plots. On July 7, the plants were thinned to approximately 27 plants per row, about 4 inches (10.2 cm) apart to provide ample room for growth. See Figure 36.
Figure 36 Carrot thinning, July 7
On Aug. 22, plant vigor was determined by measuring chlorophyll levels of the carrots in each plot. Ten readings were obtained per fertilizer plot, and the data was downloaded into a spreadsheet. The average and standard deviation was determined to arrive at the final relative chlorophyll reading. Obtaining meaningful readings was a challenge because of the small surface area of the carrot leaf.
See Table 11.
Table 11: Relative chlorophyll readings - carrots
The data above shows the AGGRAND-fertilized carrots had more measurable chlorophyll, and, hence, more nitrogen in the leaves, translating to increased vigor. This also substantiates the observations that the plants subjected to the AGGRAND fertilization program yielded larger plants and increased productivity.
On Aug. 30, the tops of the carrot plants were emerging from the soil and turning green. The soil was raked to cover the carrot tops. The AGGRAND carrots showed exceptional growth when compared to the Leading Organic and Control plants. On Sept. 6, all carrots were harvested in all plots. See Figure 32.
At the time of harvest, the leaves were cut off at the crown where the leaf stem entered the orange tap
root. The carrots were stored overnight, then weighed the next day using an AND FX3000i digital
balance, serial #: 1561035. The length of the carrot was measured using a straight edge and ruler.
See Figure 33.
Determining carrot weight
Measuring carrot length
Carrot Harvest: Row 1 results - AGGRAND and Leading Organic fertilizer
The AGGRAND fertilization system plot produced heavier carrots than the Leading Organic fertilizer plot and the Control plot; however, the Control plants unexpectedly produced more and heavier carrots than the Leading Organic plot.
Potatoes also produce well in cooler climates and are of considerable interest to many growers. Considering the small plot size, the 2010 yield was excellent, with the AGGRAND plot being the most productive. In 2011, the study was repeated with changes in the specific location within the planting beds and the cultivar grown (Kennebec). The seed potatoes were planted on May 11. On June 1, plants had emerged in all plots. On June 6, 20 of 24 seed potatoes had emerged in the AGGRAND and Control plots, while all 24 plants had emerged in the Leading Organic plot.
No cut worm infestation appeared in these plots as was experienced in the broccoli and tomato growth areas. By June 24, all potato plants had emerged, totaling 24 in the Leading Organic and Control plots, and 23 plants in the AGGRAND plot. Plant vigor was determined on June 24 by measuring chlorophyll levels of the potato leaves. Each plant per fertilizer plot was scanned, and the data was downloaded to a spreadsheet. The data was averaged and the standard deviation was determined to arrive at the final, relative chlorophyll reading. See Table 13.
Table 13: Relative chlorophyll readings - potato plants
The data above shows the AGGRAND-fertilized plants had more measurable chlorophyll, and, hence, more nitrogen in the leaves, translating to increased vigor. This also substantiates observations that the plants subjected to the AGGRAND fertilization program yielded larger plants, earlier and more blooms, with earlier and more prolific fruiting in comparison to the other growth plots. The plants were flowering throughout the month of July. The potato rows were mounded or hilled on July 5 to facilitate potato formation higher on the stem, enhance potato formation in loose soil, reduce the green alkaloid formation on the potatoes and reduce weeds. Hilling was done in all plots.
Figure 35: “Hilled” AGGRAND potato plants
Photos taken on July 13 show exceptional growth of AGGRAND-fertilized plants in comparison to the Leading Organic and Control plants. See Figure 36.
As the days shortened, some plants showed yellowing, but were overall prolific up to harvest. On Sept. 9, potatoes were harvested in all plots. See Figure 37.
Figure 37: AGGRAND potato harvest plot
The potatoes were weighed on Sept. 12 using an AND FX3000i digital balance, serial # 1561035. Maximum length was determined using a straight edge and ruler. See Figure 38.
Measuring maximum length
Table 13 summarizes the potato harvest.
Compared to the two competitive plots, the AGGRAND plot produced a substantially greater number of tubers and higher total potato weight. The Leading Organic fertilizer produced a greater number of potatoes than the Control plot, but produced on the average smaller potatoes, to finish last in total harvest weight. It was unexpected that the Control plants would produce on average slightly heavier, larger potatoes than both plots.
Tables 14 and 15 summarize the entire harvest by number of vegetables and total harvest weight and compares the production of AGGRAND fertilizers with that of the Leading Organic fertilizer.
With the installation of the Davis Instruments weather station, growing conditions were documented on a per-hour basis and compared with historical data to obtain an understanding of why plants are more or less responsive from year to year.
Graph 1Historical weather data for the period from 1909 to 2010 was obtained from Dr. Edward J. Hopkins, assistant Wisconsin state climatologist. The data was acquired by observations in Superior, Wis. at position 46.70°N, 92.02°W, approximately 4.25 miles (6.84 km) southeast of the AGGRAND growth plots, which are located at 46.73°N, 92.11°W. Temperature and precipitation comparisons covered a period from May through September where these parameters have the most influence on plant growth.
See Graphs 1, 2 and 3.
Growing conditions in 2011 were initially cooler compared to the average; in fact, May and June’s average maximum temperatures were markedly less and growth was limited during this period. Average minimum temperatures were higher than the long-term average. The overall temperature during the period from May through September was slightly higher, which allowed the crops to make up for the lagging growth earlier in the season.
As revealed in Graphs 4 and 5 below, precipitation during the 2011 growing season was substantially less than in 2010 when a number of heavy downpours marked the growing season and contributed to the excess. Nevertheless, watering was required on only two occasions in 2011 because rain fell at timely intervals. The period from mid-August through the end of September received little rain and substantially less than the average amount since 1909. Overall, however, precipitation during the 2011 growing season was slightly above average.
Soil respiration is an indicator of microbial activity and soil health. This was measured to determine if one fertilizing regimen was more effective in obtaining a response from the soil microbial community. On April 22, a 96-hour respiration study was conducted to measure the microbial activity of the freshly tilled growth plot soil. Samples from each quadrant were measured and recorded and are summarized in Graph 6. After 24 hours, the AGGRAND samples demonstrated increased respiration over the other plots and substantially higher than the Leading Organic fertilizer. The Control plot was slightly lower after 24 hours, but exceeded the AGGRAND plot by a small amount after 96 hours. See Graph 6.
With any cropping system, there is removal of vegetation in the form of fruit and/or supporting plant materials. After each growing season, most of the vegetative materials were introduced back into the plot. Soil analyses are conducted at the beginning and end of every growing season to determine the relative health of the soil, the impact of the crops on the plot and whether the fertilization programs maintain or enhance nutrient levels.
Since April 2010, the soil in all plots has not received any inputs with the exception of the fertilizer application in the AGGRAND and competitive plots. Only water has been introduced to the Control plot. Soil samples were taken in April 2010 before inputs had been introduced and in October 2010 after a complete growing season. Similarly, soil samples were taken in April 2011 and September 2011.
Comparing the virgin soil sample taken during April 2010 and the latest soil samples from September 2011, all plots exhibited slight increases in organic matter, pH, bicarbonate phosphorus and cation exchange capacity (CEC). On the other hand, because of the mechanisms of plant growth and natural weathering processes, a number of soil nutrients decreased in all plots. Nitrate nitrogen and sulfur were reduced along with the micronutrients, iron, copper and boron. Sodium, which is highly leachable, also was reduced, most likely because of precipitation and water movement through the soil. Levels of phosphorus, potassium, magnesium and zinc increased in the AGGRAND plot compared to the soil in the Control and competitive plots. See Graphs 7 - 10.
The AGGRAND fertilization program, as outlined in The Gardening Guide (AMSOIL, 2010) increases vegetable yield in terms of number and total weight when compared to the Leading Organic fertilizer and the Control plot with no fertilizer inputs. Some of the AGGRAND vegetables were slightly smaller in terms of weight and size than the Control and Leading Organic produce, but not significantly.
The Leading Organic product used in this study is comprised of a blend of liquid hydrolyzed fish and seaweed that readily mixes with water and is easily applied. Application frequency is also straightforward by the addition of the product every two weeks during the growing season. The AGGRAND system enhances the soil environment and provides necessary nutrients, and requires the grower to monitor plant growth, flower bloom and fruit development for timely fertilizer applications.
Nitrogen, phosphorus, and potassium ratios (N,P,K) of the fertilizers employed in this study were 4-3-3, 0-12-0, and 0-0-8 for the AGGRAND program, and (2-3-1) for the Leading Organic fertilizer. Both fertilizer systems publicize the products as natural or organic. Both are said to influence the soil in similar ways. The Leading Organic product recommends a dilution significantly lower than the AGGRAND products, which is apparent when the products are mixed with water. The Leading Organic produces a translucent liquid; while the AGGRAND product yields an opaque mixture that provides more nutrients to the plants and soil. Again, mix ratios followed in this study are taken directly from the manufacturer.
The germination rate of the indoor tomato and broccoli starts appeared to be inhibited this year. Heat mats were employed, as in 2010, but the temperatures and the evaporation rate seemed to be higher. The increased temperatures and dryness of the soil could have produced higher than ideal soil salinity levels that possibly inhibited seed germination. To reduce future germination issues, heat mat thermostats will be used on the tomato and pepper starts in 2012.
In 2011, new analytical tools were used to provide more data and understanding of the growth plots, plants and surrounding environment.
First, the addition of the weather station to measure weather conditions was crucial as this data is essential in any research of this type. More important however, was the monitoring of soil moisture and temperature to determine optimal times to irrigate. The moisture data was used for tomato watering and could have been employed sooner judging by the leaf drying in the plots; however, while the dryness of the AGGRAND plot was high, the plot continued to show lush vegetation throughout, while the other plant leaves showed drying the week before. This is an indicator that AGGRAND fertilizers, especially the kelp and sulfate of potash components, aid plants’ resistance to drought by strengthening the cell wall.
Second, chlorophyll measurement was a useful tool to monitor plant vigor. In all cases, the AGGRAND plants demonstrated increased chlorophyll levels, directly correlating to improved vigor with higher yield. The Control and Leading Organic plots followed the same correlation with the exception of potato yield; the Control, chlorophyll readings slightly lower than the Leading Organic plants, but Control production was higher than the Leading Organic plot.
Third, soil respiration proved to be an important tool in determining soil health. After 24 hours the AGGRAND plot revealed increased microbial activity through carbon dioxide respiration, indicating more soil microbes processing organic materials and making them available for plant uptake. This test’s accuracy is dependent on consistent soil moisture levels. In 2012, a more detailed approach will be taken to evaluate these soils by drying the soil samples and then wetting them with a specific amount of water during the test. In addition, separate sample jars and paddles will be used for the 24-hour and 96-hour tests.
Finally, test plot soil fertility has now been determined on four occasions; at the beginning and end of the 2010 growing season, and twice during the 2011 season. Soil analyses obtained thus far reveal AGGRAND fertilizers contribute to and maintain soil fertility, and provide the plants with enough nutrients to sustain healthy growth. The Control and competitive plots showed a steady decline in a number of key soil nutrients. Decreasing nitrogen levels necessitated the addition of composted manure to each growth plot this fall.
The perception persists that organic or sustainable growing systems mean crops can continually be removed from the land without the addition of any supplemental nutrients. This is simply not true. Two growing years have provided good yield from all plots, but the steady decrease in some nutrient levels, most notably nitrogen, indicates that some management of soil amendments must be considered. This principle applies to the gardener and to the large-scale farmer: Continual harvest with no inputs will, over time, render the soil ineffective. On the scale used in the AGGRAND growth plots, addition of amendments is quite easy. Larger growing areas require more thoughtful consideration of crop rotations and cover cropping as an alternative to chemical fertilizers, herbicides and insecticides. (Mohler, 2009) Continued study must be done to determine the long-term effects of growth and fertilizer applications on these plots.
Albrecht, W.A. (1996). The Albrecht papers. (Vol. 1). Metairie, LA: Acres U.S.A.
AMSOIL INC. (2011). 2010 Vegetable Productivity Study. G-2851. Superior, WI: AMSOIL, INC.
AMSOIL INC. (2010). The gardening guide. G-1292. Superior, WI: AMSOIL, INC.
Carson, T., (2004). Golf Course Management. 72: 28.
Havlin, J.L., J.D. Beaton, S.L. Tisdale, and W.L. Nelson. (2005). Soil fertility and fertilizers, an introduction to nutrient management. Upper Saddle River, NJ: Pearson Education.
Haney, R. L., W. F. Brinton, and E. Evans. (2008). Soil CO2 respiration: comparison of chemical titration, CO2 IRGA analysis, and the Solvita gel system. Renewable Agriculture and Food Systems. 23:1–6.
Haney, R. L., W. F. Brinton, and E. Evans. 2008. Estimating soil carbon, nitrogen, and phosphorus mineralization from short-term carbon dioxide respiration. Communications in Soil Science and Plant Analysis.39: 2706-2720.
Kinsey, N. and C. Walters. (2009). Hands on agronomy. Austin, TX: Acres U.S.A.
Mohler, C.L. and S.E. Johnson, ed. (2009). Crop rotation on organic farms: a planning manual. Ithaca, NY: Natural Resource, Agriculture, and Engineering Service
Moyer, J. (2011). Organic no-till farming. Austin, TX: Acres U.S.A.
Murdock, L., D. Call, and J. James. (2004). Comparison and use of chlorophyll meters on wheat (reflectance vs. transmittance/absorbance). Lexington, KY: University of Kentucky Extension.
NASA. (2011). Chlorophyll Meters Aid Plant Nutrient Management. Available at: http://www.sti.nasa. gov/tto/Spinoff2009/er_10.html
National Stone Association. (1986). Aglime fact book. Washington, D.C.: National Stone Association.
Senn, T.L. (1987). Seaweed and plant growth. Clemson, SC: Senn.