Answer: The typical life span of a fruiting quince is 35 years, so you might have quite a survivor there! You didn't mention how much fruit you are getting, but a mature quince tree produces only about one bushel basket of fruit, so your tree may be performing well. The fruit size can also be determined by its variety, and not something you can influence greatly. Quince like well-drained soil and full sunlight. Since you say you "discovered" it, are other trees shading it? That could be a factor. Unlike many fruit trees, quince doesn't need much, if any, fertilizer. Be careful not to overfertilize with nitrogen. Nitrogen produces lush growth, which is susceptible to fireblight disease in quince. If you want to fertilize in spring, use 10-10-10 or 5-10-10. The guideline is 1/8 of a pound per year of growth, up to a maximum of 5 pounds. Water thoroughly before and after applying to prevent root burn. If there are dead branches, prune it out in late winter/early spring. If this is your first year with the tree, I'd recommend watching to see what it does before pruning any more drastically (next year). I hope this info helps!
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