I did not say anything about adding lime in my brief post about Ixiolirion tataricum. But I note a number of replies are all about adding lime, increasing pH, etc. Plants sometimes need calcium and cannot take it up if it's not in solution. To be in solution, it's got to be dissolved from a water-soluble salt, e.g., Calcium Carbonate, Calcium Nitrate, etc. Lime is not limestone, nor is all limestone dolomitic. They always need a source of magnesium. Dolomitic limestone is a major source of magnesium which is the inorganic element around which the chlorophyll molecule is organized just as iron is the inorganic element in the hemoglobin molecule. Each is central to the organization of these principal molecules that differentiate animals from plants. We bleed red, plants bleed green. Plants die if they can't pick up enough magnesium. (Very rare), but occasionally a growing mix may make particular plants struggle unnecessarily. Very alkaline soils make many plants die. And as noted, most plants do very well in a slightly acid or neutral soil. Of course many acid-loving plants, e.g., the heaths, cranberries, can be found growing over limestone,falling leaves and leafy detritus from evergreens tend to become acidic as they rot and degrade into new soil. Let's clarify our thinking here and not insist on accuracy only in the area of trying to establish boundaries for taxonomic niceties that don't mean much except to taxonomists and those of us who have to put up with them to talk understandably to one another.