Answer: You have me stumped. It sounds like you are following good gardening practices, rotating the crops and feeding the soil and you have had good results before so we can pretty much rule out the most obvious problems. Assuming you have done "nothing different" (new source for transplants?), and the Park District did "nothing different" (did they lime last fall?), and your neighboring gardeners did "nothing different" (spray overdrift or volatilization on a hot day?) then it would need to be caused by either the weather or the soil ( a new mulch or a drift in pH over time or a new bedding used for the bunnies?) or possibly a change in watering (such as equipment or source?) or .... To begin trouble shooting I would look for any changes similar to those I've noted, then look to the soil. You might consult with your county extension and run some soil tests to see if anything unusual shows up and also to see if they have any possible explanations. I'm sorry about your garden!
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