A community garden is a communal organizational project aimed at developing the local standard of living and the environment, focused on one physical demarcated area. The community garden is established and maintained by and for the community members, encourages inter-social activity and is open to all.
The community garden is managed by the local residents and allows for creating and strengthening communal bonds, immediate access to nature and the earth, and promotes urban sustainability. The garden strives to be accessible and inviting to the entire community, to sustain a long-lasting work day commitment (preferably, weekly) and to serve as a center for an assortment of communal and environmental activities.
Of course, the community garden has tremendous ecological value, but beyond that, it also has social value as well. The community garden is established by local community members, incorporates interaction between otherwise disconnected community members and provides open-access to all.
The community garden enables the creation and strengthening of a community, allows immediate access to nature and the earth, and promotes ecologically-minded living, even in an urban environment.

Leket (gleanings):
Leket pertains to the small amount of wheat stalks that fall in the field during the harvest. According to Jewish law, if one or two stalks fall, the land owner must leave them for any poor people who wish to collect them, however, if three stalks fall together, they are not considered leket and the owner may gather them. If the owner did not leave the leket stalks, and continues to grind the wheat into flour and make bread, the laws of leket will still apply, and the owner must give the baked bread to the poor.
Shechecha (forgotten produce):
This refers to agricultural produce that was forgotten in the field. The Torah commands the land owner to leave it for the poor. According to Jewish law, shechecha applies to one or two (but not three or more) sheaves of grain (or other groupings of agricultural produce) and would not be located by the owner unless they would search specially for them. Therefore, any grouping of produce that is stored in way that the owner would not forget them (for example: its location, its shape, or content) is not considered shechecha and the field owner is not required to leave it for the poor.
Peah (corners):
The refers to a small amount of plants that grow in the field’s corner. The field owner must not reap it, and leave it there for the poor. There is no quantity prescribed by the Torah, however, Rabbinical decrees set the amount at one-sixtieth. The owner is forbidden from saving the peah for one particular poor person. The rule is: first come, first serve. The poor person may not “reserve” the peah produce for himself, and may not mark it with by spreading his garment over it. Even if this was done, any other poor person has the right to claim it.

The Shmita (Sabbatical) year occurs once every seven years. The literal meaning of the Hebrew word “shmita” is to leave, abandon, rest. During this year, we are commanded to release our hold on our physical properties, refrain from agricultural activities, and allow the land to “rest.” While doing so, we also are commanded to enjoy the growth of natural produce and to allow all, man and beast, to partake in the field’s bounty.
The Torah commands the land owners to refrain from all agricultural work and allow the land to “rest.” During this year, the Sabbatical commands are enacted, which forbid any form of human endeavor associated with enhancing the natural growth of produce.
The Shmita year, much like other Jewish holidays which demand a form of rest (Shabbat, Yom Kippur – the Day of Atonement), there is also a sense of maintaining balance. After six years during which the land is managed in a never-ending developmental race of improvement and achievement, results and monetary benefits, the Shmita year brings about a turn-around change. The Shmita enables an opportunity for restarting, and a chance to bring about more equality to all residents, and for assisting the poor and needy.
(Taken from the JNF website)