【正文】 oduced. Only Osmocote 18612 and Polyon produced fewer florets per stem than the control treatment. Linear contrast showed that fertilizers with a NPK ratio of =9::5 (NP2O5K2O=1:1:1) produced significantly fewer floral stems than fertilizers with a NPK ratio of=7:3:6 (NP2O5K2O=3:1:2). Plants that were not fertilized were extremely chlorotic and spindly while all the plants treated with fertilizer were green and full. Fertilizers with lower P and k, such as Osmocote 19612, produced a yield of total floral stems and florets statistically equal to the nonfertilized control, but with significantly greater fresh weight and no chlorosis. Therefore, in the subsequent experiment we pared this fertilizer with HighN 2448, a fertilizer containing even lower concentrations of P and K. We also tested the effects of differet rates of fertilizer, corresponding to low, medium, and high rates based on the manufacturer’s label remendations. The yield in total number of floral stems ranged from to , but differences were nonsignificant. However, contrasts showed that plants fertilized with Sierra HighN 2448 yielded more total florets than those fertilized with Osmocote 19612, particularly at the low rate. Plants fertilized with Osmocote 19612 were heavier and had more vegetative stems than those fertilized with Sierra HighN 2448 (Table 2). Fresh weight and number of vegetative stems increased with increasing rate of fertilization, with the highest response to a high rate of Osmocote 19612. At the end of the experiment, the nonfertilized plants were very small, chlorotic, and had few stems, but were still flowering. Plants that receive the low rate of either fertilizer exhibited some chlorosis on the lower leaves. Plants were smaller and produced fewer flowers in the second expriment than in the first, because the production phase was shorter and the plants wre smaller at the time of RCF application. Argo and Biernbaum (1993b) demonstrated that topdressing with medium to high rates of RCF supported continued bloom of for at least 12 weeks. Alstroemeria plants in the second expriment continued flowering for 16 weeks and plants were still producing flowering stems at the final harvest, without any fertilizer. Both experiments demonstrated that marketable potted Alstroemeria can flower for several months without the use of any fertilizer. This is in striking contrast to the results of Argo and Biernbaum (1993b), who observed a rapid decrease in flowering of unfertilized Impatiens walletiana. We suggest that this reflects the remobilization of nutrients from Alstroemeria storage roots to supported flowering. However, nonfertilized plants were much smaller than fertilized plants and extremely chlorotic, indicating inadequate nutrition in the absence of fertilization. Unfertilized plants weighed less and produced fewer vegetative stems, but not fewer floral stems, demostrating that mineral nutrition strongly influences the partitioning of assimilates into reproductive vs. vegetative growth. Minimizing the number of vegetative stems while maintaining high production of flowering stems would be desirable for Alstroemeria, especially those grown for cut flowers, because excessive vegetative stems should be removed from the plants to increase light intensity in the interior of plants (Bridgen, 19