Can you plant a garden near septic system?

Provided that you don't have a leaky septic tank or flush uranium down your toilet, I should imagine a fruit tree would do quite well in that expanse of soil. In the event of either of those two situations, a fruit tree would be the least of your worries. While it will grow well and flourish above or near your septic tank, it would be a mistake to plant any large shrub or tree within 30 feet or maximum root length from your septic tank. One of the primary causes of blockages and back-ups is root encroachment. It might take a few years for the problems to develop, but they will.