The potential of Amsterdam’s urban infrastructure for city farming

GROWING FOOD IN URBAN ENVIRONMENTS from CITIES on Vimeo.

One of the key tasks of Farming the City was to explore Amsterdam’s existing urban infrastructure, store and to evaluate its potential for city farming. We also considered, ambulance again with reference to the Amsterdam cityscape, how to maximise the many benefits urban agriculture can bring to the city.

Plants have a positive effect on the urban environment in many ways: they help to filter the particulates in the atmosphere that contribute to air pollution, to dim city noise, to clean polluted soil and to cool the urban environment. And, of course, they are a source of potentially healthy, affordable local food; and the basis of a local food system that provides employment, generates income and supports social equity.

In exploring ideas that support better ways of urban living, this investigation focuses specifically on what types of food could be grown, in which locations, in an urban landscape. It was carried out in the city of Amsterdam, yet the outputs and outcomes have relevance for many urban settlements with a similar context.

This project is based on work carried out by the Social Design Lab for Urban Agriculture, URBANIAHOEVE, which provides insight about the creation of city foodscapes by local participants through the transformation of neglected, underused, or over-paved urban sites.

We have identified different urban types, or typologies, that offer potential for food growing and harvesting in Amsterdam. We used the existing cityscape as a basis for investigation: by biking through Amsterdam, making use of local knowledge, speaking with people in the streets and taking note of the current and potential usage of urban spaces such sidewalks, facades, balconies and empty lots, we conducted an analysis of how neighborhood spaces across the city could be developed to support urban farming.

Which typologies did we find relevant for urban farming in Amsterdam?
_Façade: one side of the exterior of a building.
_Sidewalk: A path along the side of a road.
_Balcony: A platform projecting from the side of a building.
_Gap: Empty space in between building masses.
_Stair: a series of steps for passing from one level to another.
_Greenhouse: a building that heats up inside where plants can be grown.
_Landmark: An easily recognisable site or structure; literally a geographic feature that aids wayfinding.
_Espaliers: trees and shrubs that grow horizontally, trained to catch as much sunlight as possible.
_Planters: pots with soil where trees and shrubs with small root systems can be grown.
_Paving: ground cover that makes it easier for traffic to move over a surface.

The problem with paving in a city is that it often too extensive. Paved surfaces enhance mobility and require little constant maintenance, but when a majority of the ground surface is paved we lose the ability to keep soil fertile and productive. Paved surfaces also impede water run-off, meaning that rain cannot filtrate the soil, and which frequently leads to flooding after a heavy downpour. Paved surfaces also attract and absorb heat (the urban heat island effect) and cause city temperatures to increase significantly. Take New York City’s heavily developed Times Square, for example, which absorbs great heat from the sun and, with its skyscrapers blocking refreshing breezes, sizzles like an oven in high summer. Yet the nearby waterside parks along the River Hudson remain cool; the greenery provides shade and breezes cool the air. The evidence supports our perceptions: in NYC, during summer heat waves and at night when wind speeds are low and sea breezes are light, the city’s air temperatures can rise as much as 5 degrees celsius higher than in surrounding areas (NASA).

Our analysis also considered interventions that could be carried out in Amsterdam to deliver significant environmental improvements. Increasing the vegetated land surface, for example, impedes city heating: vegetation offers high moisture levels that cool the air when the moisture evaporates from soil and plants. We explored how city greening could work; Debra Solomon, the founder and executor of URBANIAHOEVE, has shown that not all vegetation has equal value: perfect lawns, for example, offer little environmental benefit. Research shows that birds, bees and butterflies are attracted to grasses mixed with flowers such as clover. Such mixed greens are just as useful as lawns for picnics or dog walking, but offer much more to the city.

A contemporary housing project at the Herman Akkermanpad in Zeeburg, Amsterdam, shows that careful planning is needed to add environmental value. In this case, the developers aimed to attract birds and bees to the site, only to fail because the design wasn’t well thought out from the beginning. The distance between the house façades, where many beautiful birdhouses are installed, and the trees and lawn is too great for the young birds to cope with, resulting in them crashing onto the pavements during their first flights. The project, which features a large grass-only lawn, also failed to create enough spaces where animals and birds could find food.

We also investigated the role of temperature in city farming: and identified suitable spots across Amsterdam’s cityscape in which plants, fruits and vegetables can thrive. When finding places to grow food in a city we tend to focus mainly on sunny places, as they provide good living conditions for most of the plants we want to grow. Certain plants benefit from the sun, gaining warmth and shelter when they are trained horizontally against a façade. The pear would be an ideal fruit to grow in Amsterdam, when cultivated in this espalier form. Pears require a warm atmosphere, but do really well when adapted to the Dutch climate in this way. Yet one group of plants that don’t need sun and warmth are mosses; they thrive in shaded places. And where other plants often require particular soil conditions, extra irrigation or construction support (for example, to grow vertically), the moss family needs few special conditions, apart from shade, in which to grow. Simply adding milk or yoghurt directly to the soil/surface will help mosses to grow well.

Although few mosses are edible, they offer great benefits due to their positive support for their biotope – an area of uniform environmental habitat providing a living space for a specific group of plants and/or animals. In the case of mosses, it is the biological community that benefits. Another advantage is that mosses, when grown vertically, add an attractive palette of color to urban facades, turning the city into a more human and welcoming place.

For our investigation of different urban typologies, we focused on several plant families that would thrive in the urban conditions we found across Amsterdam.

Rosaceae Rose family
These plants can be herbs, scrubs or trees. Most are deciduous, which means they release their vegetation at maturity, so do not stay in leaf during the winter.

Examples: Many edible fruits (apples, apricots, plums, cherries, peaches, pears, raspberries and strawberries), almonds, ornamental trees and shrubs (such as roses, meadowsweets, photinias, firethorns, rowans, and hawthorns).

Solanaceae Nightshade family
This is a family of flowering plants that contains a number of important agricultural crops. These plants can, as with the rose family, take the form of herbs, shrubs, trees and sometimes vines. Many species are edible, most commonly the fruit of the plant. This family doesn’t mix well with the rose family. They should be placed in different planters or areas of a garden.

Examples: Chili pepper, eggplant, garden huckleberry, wolfberry, ground cherry, potato, sweet pepper, tomato.

Brassica Cabbage family
This is a genus of plants that are collectively known as the cabbages or the mustards, also known as cole crops. Most of them are annuals or biennials, which means they only grow for either one two years. Almost all species and their different elements have been developed for food.

Examples: Root (rutabaga, turnips, radish), stems (kohlrabi), leaves (cabbages, brussels sprouts, rocket), flowers (cauliflower, broccoli), and seeds (many, including mustard seed and oil-producing rapeseed). Some forms, those with white or purple foliage/flower heads, are also grown for ornamental functions. Radish and rocket, in particular, are great examples of plants that can be grown in planters on a balcony. They grow really quickly and can be harvested several times a year. They are at their best in winter and spring. They are tolerant to the nightshade family.

Chenopodium, part of Amaranthaceae family Goosefoot family
These occur across the world and are mostly a perennial species, which means they live for more than two years.

Examples: Spinach and chard. The interesting thing about these species is that they can process and remove pollution from the soil. The plant should, in these cases, not be used for food, but they offer a great way to clean polluted soil in an urban environment. They also are suitable for growing in planters.

Asteraceae Sunflower family
This is the largest family of vascular plants, which means that these plants can conduct water, minerals and photosynthetic products. Ferns, club mosses, conifers and other seed-bearing plants are also part of the vascular plant group. A significant number of these species are shrubs, vines and trees. There are also plants within the mosses group that remain edible as they are able to absorb pollution from the soil, for instance mushrooms. The disadvantage is that these may not grow quickly: as patience is required, this might not be the best choice for city growing where space is limited.

Examples: Artichoke and sunflower.

During this investigation, we have outlined the great potential that Amsterdam’s urban infrastructure offers for city farming. We have described which places can be used for cultivation, and what types of plants do best in which sites. We look forward to taking this investigation a step further: by getting practical and developing city farming across Amsterdam.

Posted on 30 March 2011 and filed under content

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