Gardening Opportunity Sought (Argall Avenue Industrial Estate E10)

We live in a flat that has a balcony but is without any garden. We applied for an allotment space around 7 years ago and went on the waiting list but with no result as of yet. My children currently aged 10 and 12 are still very much interested in gardening and growing common vegetables and fruits. We would be happy to share the harvest with the owners of the garden. If there is anyone with a garden plot who might have even a small area that they could allow us to do some growing on - that will be very much appreciated. Not sure how often we would need to be around. It probably suits and elderly or retired person the most. Of course we would bring our own equipment/seeds etc. I do hope to hear from someone soon - Thanks.