It's the least you can do. Consult the chart of VMU items for what the effects of feeding these to your A-Life will be. The random event item, though, will make it very unhappy. Everything else will have its normal effect. All food vanishes upon leaving the Chao Garden.
Coconuts regrow indefinately.
An A-Life will eat any food if it wanders into it. If an A-Life is just sitting quietly, it may be tired, or just uninterested in doing anything. An A-Life waving its arms directly in front of you wants to be petted . An A-Life thrashing on the ground crying is throwing a tantrum. Feed it coconuts to calm it.