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The neglected diversity of immigrant gardens in Germany - examples from Bonn
Gardening techniques and plant preferences
Some of the home garden areas are used jointly by several families. There are no
hedges nor fences to separate these gardens sometimes. Paths between the “beds”
do not exist. Each square metre is used to grow something. If there is space outside
the own garden, people enlarge their cultivated territory by planting less valuable
crops which are needed in larger quantities in front of them: beets, corn with beans,
peas, kale, pumpkins. To get the maximum yield from as many plant species as
possible, the gardeners apply a system of intercropping and crop rotation throughout
the year. There is scarcely ever open soil except some weeks during winter time.
Depending on the size and position of the gardens, the people dig manually or
plough with larger machines. As early as possible, broad beans (Vicia faba L.) are
sown, and between the rows other crops are later sown, e.g. potatoes. Squash and
pumpkin cover the same ground at the end of the growing season. This enables the
people to have up to three harvests per year from one piece of land. Yellow-eared
corn land races (Zea mays L.) are frequently grown together with climbing and runner
beans, cucumbers, and pepper (Capsicum spp.), beet, leek, kale and lettuce (for
harvesting of seed). If the plants do not get enough light, the corn plants are partially
defoliated. The sowing is not usually done in regular lines or rows, but more
frequently in lots. Tender species are initially covered with refuse plant material, in
addition to old parts of clothing or spreads during cold and rainy days. Sowing these
crops indoors or in self-made greenhouses, such as German gardeners do, is less
popular but necessary for tomatoes (against Phytophthora-infestations), melons and
eggplants (Solanum melongena L.). In some years, the eggplants do not grow well
outdoors because of climatic factors. The gardeners continue growing and selecting
early ripening types thus, trying to adapt the crops to the new environmental
conditions.
The intraspecific diversity is extremely high in garden beans. It seems to be the most
important vegetable species found in immigrant gardens. They have two common
uses: the young fruits are consumed as vegetables, and the ripe seeds are used as a
widespread protein source. Many special landraces exist in Bonn originating from
different cultures and countries. These landraces are exchanged between gardeners,
then individually selected and carefully propagated. Bushy types are rarely found,
because they are thought to be less tasty and lower in yield. In some cases even the
runner bean (Phaseolus coccineus L.) is used as dry bean, but only rarely and in
small quantities besides in a garden of a woman from the Philippines. She prefers to
use the young pods of this species and grows it as a long flowering ornamental and
as a permanent yielding vegetable at the same time.
For seed growing of bi- and perennial crops, the selected individual plants flower for
several years. The selected plant remains and bears seed as long as it lives. A
typical example for this technique is the so-called black kale (Brassica oleracea L.
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