Planting of green onion in Zhangqiu county of Shandong province has thousands of years of history. Green onion in Zhangqiu is well-known to the domestic and foreign market for its good taste and high quality. Balanced fertilization with potassium in the production of onion has become more and more important for both quality and farmers’ income. For this purpose, managing potassium rates and balanced fertilization field trials and demonstration on green onion were conducted.


On November 9, 2007, a harvest field day on green onion was held in Zhangqiu county. Dr. Adrian Johnston, Vice President of IPNI, Andrew Law from Canpotex, and Romina Leung from Odyssey International Trading, were invited to present at this field activity. IPNI China Program Director of Dr. Jiyun Jin and Deputy Directors of Dr. Ping He and Dr. Shutian Li also. Other participants, including leaders from Shandong Academy of Agricultural Sciences, Jinan Agricultural Bureau, Zhangqiu county government and Zhangqiu Agricultural Bureau and about 300 farmers, were involved in the field activity.

Fig. 1 Dr. Adrian Johnston gave speech at opening ceremony of the field harvest day

Fig.2 Field trials of K rates on green onion Fig.3 The King of green onion was selected and honored

Obvious differences in growth were observed in the field trials and demonstration plots. Application of potassium at 180 kg K₂O/ha and 270 kg K₂O/ha increased green onion yield by 12.1 t/ha (13.8%) and 23.2 t/ha (26.3%) over the 88.0 t/ha yield for the NP control (255-225-0). Net income was increased by US$ 1968/ha and US$ 3757/ha for the 180 and 270 kg K₂O/ha rates. Compared to the farmers' practice (259-259-259 kg N-P₂O₅-K₂O/ha), the balanced fertilization (255-225-270 kg N-P₂O₅-K₂O/ha) received 11.0 t/ha (11.0%) more yield and US$ 1784/ha more profit. In addition, potassium application helped green onion against lodging and improved the taste.


Fig.4 Farmers are striving to be the first person to answer the questions Fig. 5 One corner of harvest site of green onion


The group visited greenhouse trials of K rates on tomato and field trials evaluating K rates on winter wheat as well.
The whole program was reported by Shandong TV, Shandong Broadcasting station, and Dazhong Daily.



Fig.6 Greenhouse trial of K rate on tomato Fig.7 Field trial of K rates on winter wheat