Phosphorus availability and acid pH are major limiting factors for grass and crop production in the Andisols of Southern Chile. Sustainable management requires both the efficient use of fertilizers and the recycling of agricultural waste. The aim of this study was to investigate the effect of citrus waste, alone or in combination with beef cattle manure (CM), on phosphorus availability. Controlled laboratory incubations were carried out for up to six weeks. Lemon (L) and mandarin (M) fruit wastes were added to an Andisol, amended or not with dried CM. Fruit parts (Peel, Juice or whole fruit), and for whole fruit the size of the fruit pieces added to soil, were compared. Water-extractable (WE) P, phosphatase activity (P-ase), and pH were monitored. In general, the size and distribution of the citrus fruit wastes gave similar trends in WE-P, P-ase, and pH. Lemon induced larger effects on WE-P and pH than did mandarin. CM caused sustained soil alkalization, increased soil WE-P and P-ase. Citrus addition produced a short-lived acidification followed by net alkalization and immediate increases in WE-P and P-ase. The combined amendment with citrus wastes enhanced the positive effect of CM on soil WE-P and alkalization, with only a small effect on P-ase. These findings indicate that citrus wastes would intensify the beneficial effects of CM amendment on soil P availability and additionally the liming effect on acid soils.