• Ground based: Ground-based UA focuses on the use of vacant lots and buildings, public or privately-owned, for space to grow crops. Though high quantities of vacant land are available in cities, the land must be suitable for UA, eliminating protected spaces or other re-purposed land. This land must have adequate sunlight and space. Much of these areas are converted into community gardens, developed by initiatives such as the Urban Garden Program (Walker, 2015) and the Urban Agriculture and Openspace for the Greening of Detroit (Atkinson, 2012), both in Detroit, MI. These programs can successfully transform unused public land into greenspace to increase the supply of healthy food in urban areas, and place the focus on improving food security into communities by involving a range of local residents, from elementary school students to adults. Privately owned land also provides an opportunity for crop growth, involving the use of incentives, such as tax breaks for converting land into greenspace, or conversely tax penalties for failing to make use of the lots. Soil quality and contamination is a big issue on the ground, as pollutants such as lead or other metals may render the land unsuitable for food production (Ackerman et al., 2012). 
• Rooftop: With a high concentration of buildings in urban areas comes a great opportunity for rooftops to be transformed into productive farmland. Though land on the ground may be limited, flat rooftops are ubiquitous and largely free of the potential contaminants and weeds that make ground-based agriculture problematic. Access to high levels of sun exposure is advantageous, although challenges associated with attaining proper soil depth and nutrient levels can be difficult to overcome, as can physical obstacles such as increased wind susceptibility and transport inconveniences (Ackerman et al., 2012).
• Controlled Environment Agriculture: In order to produce year round, greenhouses can be used. They can keep climatic variables such as temperature and precipitation constant. Soil quality and nutrient levels can also be maintained, while outside contaminants can be mitigated. There are potential high-energy and material costs associated with large greenhouses (Ackerman et al., 2012). The creation of mini-greenhouses may be simpler and more cost and energy efficient (Jeavons, 2012).  

• Start with deep soil preparation to develop good soil structure using double-digging to create raised beds. Minimum size of the bed should be 3x3ft, but can be larger. The goal of double-digging is to loosen the soil to 24 inches below the surface. This technique aerates the soil, facilitates root growth, and improves water retention. After the structure has been established, double-digging is no longer necessary and soil upkeep can be maintained through surface cultivation, which loosens the upper two inches of the soil. 
• The best source to start off this soil with is compost, but it should only be added before or during the initial double-dig. Compost helps create soil fertility and provides nutrients. 
• Close plant spacing. Seeds should be planted diagonally offset or in a hexagonal spacing pattern, with equal spacing between the seeds. Seeds should be planted at a depth equal to its thickness. 
• Companion planting. Planting certain plants alongside others can improve yield. 
• 60% of the crops planted should be carbon-efficient crops, which mostly creates significant carbonaceous material for composting. Excess yield can be used for food. 
• 30% of the planted crops should be calorie-efficient, which provide a lot of calories in the form of food. 
• The use of open-pollinated seeds. This preserves genetic diversity by having no restriction on pollen flow.
• The last technique is the combination of the whole system. Every component of the system must be used together to avoid soil depletion. This is an all-in practice.  

Overall: Jeavons’ method is successful in its goals of quick soil building, using less water, and increasing crop yield. The method can end up building soil 60 times faster than would be possible in nature. It does this using 67-88% less water, over 50% less purchased organic fertilizer, and 94-99% less energy than commercial agriculture per unit of production. This method also increases soil fertility by more than double, with a 200-400% increase in caloric production per unit of area, as well as a doubling of income per unit of area (Jeavons, 2012). Only 4,500 ft² is necessary for a fully functional mini-farm.

Crop Yield Results: Specific crops may have a greater increase in yield by using this method than other crops. According to Figure 1 , vegetables such as those that are dark green or orange, dry peas and beans, and starches, as well as other vegetables, such as artichokes, all can see large increases in yield under this method when compared to conventional practices. Dark green vegetables have one of the largest differences in yield, rising from 0.49 lb/ft² to 0.95 lb/ft². The fruit with the greatest increase in yield is grapes, increasing 0.45 lb/ft² from 0.2 lb/ft² (Ackerman et al., 2012).

Figure 1: Average yield of crop based on growing method. Vegetables: Dark Green - broccoli, collard greens, escarole, kale, lettuce (leaf), mustard greens, spinach, turnip greens. Orange - carrots, pumpkin, squash, sweet potatoes. Dry Bean & Peas - dry edible beans, dry peas and lentils, lima beans. Starchy - green peas, potatoes, sweet corn. Other - artichokes, asparagus, bell peppers, brussel sprouts, cabbage, cauliflower, celery, cucumbers, eggplant, garlic, lettuce (head), okra, onions, radishes, snap beans, tomatoes, misc. vegetables. Fruits: Tree Fruits - Apples, cherries, figs, peaches, pears, plums. Grapes. Berries - Blackberries, blueberries, cranberries, raspberries, strawberries. Melons - Cantaloupe, honeydew, watermelon. Statistics in graph taken from: Ackerman, K et al. 2012

Land Area to Cultivate Average Crop Yield:  Figure 2 compares how much land is required to cultivate each crop between conventional practices and the GROW Biointensive method. The land area needed for each crop is significantly less for the Biointensive method, except for with melons. Dark green and orange vegetables, as well as grapes and berries all require less than 10,000 acres for their average crop yields, while dry beans and peas, starchy and other vegetables needed around 35,000 acres (Ackerman et al. 2012). These statistics are based on the average crop yield produced, and would not be on as large of a scale in urban agriculture.

Figure 2: Estimated acres needed to cultivate an average crop yield based on methods. Specific crops for each crop type can be found in Figure 1. Statistics in graph taken from: Ackerman, K et al. 2012

Costs: Low startup and operating costs keep the expenses of farming down. An example can be seen in the 1.5 acre mini-farm named Les Jardins de LaGrelinette in Quebec, Canada. This farm uses GROW Biointensive methods and raised beds. Startup costs were $39,000. Operations costs were minimal, as there are less mechanism and machinery costs. Another reason for lower operation costs is the lack of a need for extra workers, which usually comprise 50% of production costs. Total production can generate $60,000 to $100,000 per acre, which creates a 40% profit margin (Permaculture Apprentice, 2017). A $39,000 startup cost for 1.5 acres is equivalent to less than $3,000 for a 4,000 ft² farm. Jeavons claims that a net profit of $20,000 to $40,000 can be made off of a mini-farm of this size. The Quebecois farm is a great example that demonstrates the efficacy of the GROW Biointensive method, as it successfully reduced the financial and labor burdens of their farm, which in turn made the farm more profitable.

• Mini-greenhouses require basic tools and are long-lasting. Units are typically around 50 ft². A unit that lasts 10 years only costs $12.50 per year (Jeavons, 2012). A 4,500 ft² mini-farm can have up to 90 mini-greenhouses, which would total a yearly cost of $1,125.