Setting or editing alerts in the iOS app is very straightforward. For set-up an alert, first open the app and click on the Settings tab on the bottom right hand side of the app.
Next, you can select either Email, Push, or both alerts. To select or opt-in just click on the Email or Push icons at the top of the screen. A colored icon means it has been turned ON while grey means it is OFF. Here's an example of only the Email notification being requested.
After clicking Save, click on the Grow Rooms tab on the bottom left hand side of the app then click on the name of the room you'd like to add alert thresholds for. You'll then see MIN/MAX placeholders for each parameter. Feel free to adjust these to whatever you'd like. Remember to hit SAVE after making any adjustments.