Research conducted at Virginia Tech and the University of Maryland in conjunction with partners such as the Maryland State Highway Authority has demonstrated Bloom’s efficacy in establishing turf, crops and more in a variety of settings, from roadside soil conditions to newly established wetlands. Read more below about the research findings on Bloom’s benefits.
Scientific Field Research
Establishing Turfgrass in Poor Soil Conditions using Bloom
Chenglin Zhu and Dr. Gary Felton, University of Maryland in collaboration with Maryland State Highway Administration.
Few studies have been done on the effects of biosolids products like Bloom on poor nutrient soils, particularly roadside soil. Highway roadside soils often suffer from compaction, erosion, and poor vegetation, making it difficult to establish and maintain turfgrass.
This study, conducted by University of Maryland researchers in conjunction with Maryland State Highway Administration, aimed to assess the effects of Bloom and Bloom mixes on soil conditions and turfgrass growth. The research compared Bloom and derivative products to inorganic fertilizer applied to turfgrass in till and no-till plots designed to simulate roadside soils. Bloom resulted in significantly higher hydraulic conductivity (a measure of soil permeability) than inorganic fertilizer. A mixture of Bloom, sand and sawdust, a registered Bloom blend developed by DC Water, was deemed the most effective treatment for improving soil physical conditions and soil fertility (increasing both carbon and nitrogen).
Click here for presentation deck summarizing findings.
Impact of Biosolids on Plant Drought Resistance and Hormone Metabolism
Virginia Tech, Department of Crop and Soil Environmental Sciences, Xunzhong Zhang, Erik Ervin, Greg Evanylo, and Katie Haering
Biosolids applied at agronomic rates have been shown to improve hormone metabolism and drought tolerance in greenhouse trials; this research sought to test the effects in the field. This study looked at the effects of anaerobically digested biosolids* on hormone and antioxidant metabolism and grain yields in a corn-soybean rotation.
The biosolids product increased leaf photochemical efficiency; key plant hormones (indole-3-acetic acid and trans-zeatin riboside); proline, an important amino acid; and superoxide dismutase (SOD) activity (fighting oxidative stress) in corn and soybeans compared to controls. It increased grain yield by 77% in corn and 18% in soybean compared with the controls. “The research demonstrated that biosolids application improves leaf anti-senescence hormones, osmoprotectant, and antioxidant metabolism to increase grain yields, especially under drought stress,” conclude the researchers.
Click here for full manuscript published in Crop Science.
*Research conducted prior to anaerobic digesters being installed at Blue Plains; AD biosolids material in question was from another plant but of a similar composition to Bloom today.
Biosolids improve urban soil properties and vegetable production in urban agriculture
Odiney Alvarez-Campos and Greg Evanylo, Virginia Tech.
Exceptional Quality biosolids like Bloom may be developed into products to rehabilitate disturbed urban soils for vegetable production in urban gardens. This study sought to investigate the effects of various EQ biosolids products on urban soil properties and vegetable yield. Field research was conducted at Blacksburg, Virginia in an urban subsoil fill from a nearby construction site to simulate degraded urban soil properties. Three EQ biosolids products, including Bloom, were applied bi-annually at agronomic nitrogen (N) rates, and annually at land reclamation rates (5x agronomic N rate). A heat-dried and pelletized EQ biosolids product and inorganic fertilizer were applied bi-annually at agronomic N rate only.
Soil carbon accumulation two years after biosolids applications ranged between 37 to 84%, highlighting the potential benefit of these products to sequester carbon in degraded urban soils. Soil N availability was less than expected based on previous greenhouse research, even after cumulative biosolids rates, likely due to low organic matter and high clay concentrations that reduced organic N mineralization. Cabbage (~3.1 kg m-2) and kale (~1.1 kg m-2) yields were greater with reclamation rates than with inorganic fertilizer (1.0 kg m-2 and 0.4 kg m-2, respectively). Thus, despite limiting physicochemical soil conditions, the addition of biosolids at reclamation rates showed greater potential to increase vegetable yields after two years of application.
These findings were excerpted from a publication under review in Urban Agriculture & Regional Food Systems.
Using Bloom for Wetlands Restoration
Brian Scott, University of Maryland, Department of Environmental Science and Technology.
This study incorporating Bloom in a wetlands restoration project is still underway; however preliminary results indicate that Bloom supports plant growth in wetlands, particularly in non-flooded areas, with pioneer plants like verbena growing well with the use of Bloom. Bloom also appears to attenuate nitrate and phosphorous, which are often potential environmental concerns. However, the research indicates that Bloom is likely optimal at lower application rates (ie, closer to a target of 30 cubic yards per acre, versus 60 cubic yards per acre as is established recommendation), including to mitigate potential methane emissions. Fresh Bloom may also promote iron reduction, which is a key indicator of healthy wetlands. The researcher is conducting a field study this summer to confirm preliminary findings.
Click here for presentation deck with site photos and more details.
Other Field Experiments and Observations
Flowering Plant Trials
Dr. Frank Gouin, Professor Emeritus of Horticulture, University of Maryland
The late Dr. Gouin, a renowned horticulture and compost expert, conducted various trials of Bloom, including leafy vegetables and flowering plants. According Dr. Gouin, “Bloom is rich in iron and essential trace elements. Available iron means that plants fertilized with Bloom will develop deep, dark-green foliage. Growers at Homestead Gardens compared begonia plants grown in Bloom-amended potting medium with begonia plants growing in the same medium amended with Osmocote 18-6-12. The plants grown with the Bloom were nearly twice as large, contained many more flowers and had foliage black-green in color as compared to grassy-green for plants grown with Osmocote.” Click here for photos and more information on his findings. Dr. Gouin discusses his observations on Bloom’s benefits in this video.
Vegetable Growth Trials
Nadia Mercer, Program Director Washington Youth Garden at the National Arboretum
As reported in The Washington Post, Mercer’s team tested Bloom by comparing two beds containing cabbage and celery, one with the garden’s usual compost-amended soil and the other with Bloom incorporated. With Bloom, “they grew a lot more rapidly, they were bigger and healthier in general,” Mercer said. “I was really surprised with the difference.” It clearly drove leaf growth but not so much the development of fruits such as eggplants and tomatoes, or in root vegetables such as carrots, according to Mercer, concluding that “it’s great for leafy things.”