Effect of foliar application of boron, zinc, and iron on growth and yield of cucumber in polyhouse condition. Levels of each micronutrient (Boron, Zinc and Iron) are three (0, 25, 75).
As you stated, you want to do your experiment at polyhouse condition. Design of your project is changed according to the some factors; irrigation system, plantation from pot or land... If seeds of cucumber are planting directly from land is better to follow of RCB Design.