Clearly there are many benefits to urban agriculture. However, as our aim is to educate about urban agriculture, we would not fulfill our goal if we did not include some of the challenges and drawbacks.

Soil Contamination:

One of the tactics for successfully producing urban agriculture is using abandoned industrial land. However, due to past industrial use or urban pollution, often these sites are brownfields, or land abandoned due to contamination. The worry is that the contamination of the land and the soil will possibly endanger those working the land and/or produce contaminated food that is dangerous to eat. While the EPA does not have specific rules regarding the detoxification of brownfields and urban agriculture, it has realized this gap and provided guidelines for safe gardening and agricultural practices in contaminated urban areas. It encourages investigating the history of the land use, getting the soil tested, and remediation techniques such as soil disposal or compost integration if there is significant contamination on site. Wortman and Lovell (2013) suggest remediation techniques can be expensive and thus prohibit a wide spread of urban agriculture. However, they also address the fear of contaminated food and note that at least for lead, the possibility of contamination is not high.

Adverse Urban Conditions:

The urban environment for gardens and agriculture is different than the rural environment. The elevated pollution levels often found in urban areas includes a rise in nitrous oxide which can negatively affect plant flowering and aging (Wortman and Lovell, 2013). Higher levels of ground-level ozone which negatively impact photosynthesis exist around the outskirts of cities, possibly affecting the viability of peri-urban (on the border of rural and urban) agriculture. However, there are some benefits from the urban environment, such as increased carbon dioxide levels when controlling for temperature, which positively impact plant growth.

Environmental Gentrification:

Checker (2011) defines the term environmental gentrification as the co-optation of environmental justice principles to drive urban development. In the process of urban development, land rents increase, usually forcing low-income and minority communities to seek lower rents elsewhere. While Checker (2011) writes of policies and initiatives specifically used to increase urban development, green initiatives do not have to be aimed at urban development to spark gentrification. View this New Yorker article to read how a community garden and a non-profit were used in an attempt to encourage development in the historically low-income and minority neighborhoods in Berkeley and Oakland, CA. It is important to note that environmental gentrification does not go unnoticed. Curran and Hamilton (2012) note how residents in Brooklyn continue to protest and circumvent environmental gentrification by engaging in strategic "greening."

These challenges and drawbacks are especially important to consider in the context of food deserts. Often, it is low-income and minority residents who are subjected to food deserts (John Hopkins Magazine) and if urban agriculture is to be part of the solution, critiques must be taken seriously.