In order to have a successful farm or garden, healthy soil is a necessity. Urban farmers face challenges when it comes to this. This is due to the fact that soil may get contaminated from past use and nearby activity from unauthorized dumping, construction, heavy traffic, and being too close to buildings that lead based paint has been used. But, in some instances soil can actually be clean. The most important thing to do is to get your soil tested. The alternatives to planting your garden in the soil would be with the use of raised beds or containers over paved surfaces. The other problem that urban farmers may run into is extremely compacted soil with low fertility (UCANR). Raised beds are boxes that can be built from material free of harmful chemicals and then filled with organic soil. This will provide the plants with proper nutrition to be successful. By using raised beds, the urban farmer will also eliminate any soil compaction from foot traffic as well. The installation of a membrane or bottom barrier in the garden bed will also be a great way to take extra precaution to ensure no contamination is done. It is also beneficial to add compost to the soil to aid in healthy and productive plants. is one of the most common practices used by gardeners on urban soils. This practice of using compost provides an increase in organic matter, a source of slow release nutrients, an increase in water-holding capacity, a clean growing medium, and a dilution of potential trace metals in the soil (USDA). In addition, urban soils often have higher levels of metal present because of human activity on the soil. Gardening in urban soils could potentially increase exposure to the metals if you swallow or breathe in the soil particles or if you eat food grown in the soil. These types of metals include arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. Although certain metals are essential in small amounts, large amounts of them can lead to health concerns. In particular, lead is a major concern for health problems, especially for children. Usually in urban soils, it is not uncommon to find types of metals near or above guidance levels present in the soil. Health risks that are associated with metals in soils at a level that is slightly, or moderately above guidance values cannot be ruled out, but are usually seen to be at a lower risk. These metals can also lead to issues with plant health as well. Some metals like copper and zinc are taken up by plants and are actually toxic to the plant. Although other metals may not cause the plants harm, they are definitely a point of concern for the health of the public. Additionally, some metals are not as easily taken up by the plants in the conditions found in gardens. In order to reduce exposure to metals in your garden it is important to add compost into the soil. This can help keep metals in the soil from being taken up (Cornell University).
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Let's Talk Urban Ag 
I have also wondered about what the quality of the soil is like in urban gardens since they are usually in an environment that has been the victim of pollution from various sources! I think it is very important that urban farms and gardens test their soil before they begin to plant anything on that site. For my soil science class, I had to bring a soil sample from my house to a laboratory where they tested my soil. I ended up getting the results emailed to me, and those results were very helpful since it told me what nutrients my soil had as well as what nutrients it was lacking in. With information like this, I feel like that would really benefit urban farms/gardens. They could see whether or not their soil is fertile or healthy enough to grow plants in. This is especially important since the soils in urban areas are susceptible to contamination. I thought that your suggestion of urban farms growing their plants in raised beds is a very good idea. I personally think that the raised beds are better since they are not being directly planted into the ground, and the fact that they can be filled with organic soil or planting mix or compost is a plus! That will ensure that the plants being grown on that site will be able to grow on soil that is not contaminated. It is also very important to be aware of metals that are present in the soil on the site if an urban farmer plans on planting directly in the land. I did not know that the presence of some metals in soils can be hazardous to plant health. That is something that urban farmers should definitely keep in mind.
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Searcher/ Synthesizer
Fixing Soil Contamination
I have always wondered what it takes to clean up or fix soils that are heavily contaminated. Here is a video in which a site manager is working on the remediation of the site’s soils. It is not for an agricultural use however, it is in the urban setting. You will see that it is an empty lot in which most times urban agriculture can and will take place on. The lot is saturated in arsenic and other dangerous pollutants like asbestos. In this site they found the easiest way of fixing the soil is simply to replace it all with new soils that are not polluted.
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