This paper presents and accounts for an under-explored constraint against sprouting from sub-clausal ellipses. The account begins from the claim that antecedents for ellipsis can in principle be recovered from the syntax or an implicit question meaning. Different kinds of ellipses, however, may be subject to limits on this flexibility for antecedent recovery. I argue that these limits can conspire to block the licensing of ellipsis, specifically in the case of sprouting from an elided predicate. Moreover, I propose that these are expected consequences of the model of focus-based semantic redundancy that is found in Rooth 1992a,b. The remainder of the paper explores the diagnostic utility of sprouting in determining the size of an elided constituent. Case studies from Stripping in English and Modal Complement Ellipsis in Catalan and French are presented.