OE


Calumny is a misrepresentation or slander, produce (as a noun) is a product, usually agricultural, and a morass is a marsh or a confusing and difficult situation. Since the text is discussing growing vegetables, the only possible answer for Blank (i) is produce.
For the second blank, acreage means an amount of land, a nadir is the lowest point, and a quagmire is a situation that is difficult to extract oneself from. In the context of planning your garden, only acreage makes logical sense.
The last blank needs a word that means the vegetables that have grown. Concurrence is a convergence or simultaneous occurrence; fruitage is the harvest or yield, usually from an agricultural endeavor, and exculpation an acquittal. Again the correct answer should be obvious - fruitage is the only word that fits.