At the household scale, how does a family that grows food in a garden for their own consumption
demonstrate some but not all of the principles of fair trade?

A family who produces its own food is engaging in fair trade to the extent they are trying not to exploit others, but they may take an economic opportunity away from traditional producers and families can sometimes use child labor to help harvest and care for their products for consumption.

Explanation:

A family that grows its own food for consumption is practicing some of the principles of fair trade because they are producing something themselves and not exploiting anyone by paying low prices for produce.  However, producing your own food occurs out of the capitalist system to a large extent, although you would also have to look at how the family procures its seeds, fertilizers, etc to assure these are also fair trade products. It might undercut existing producers if everyone starts growing their own produce instead of engaging in fair trade in areas traditionally dependent on particular agricultural products for example.