Last time we did a soil test for the garden was about 3 years ago and it ranged from 7.0 to 7.5 approx. with samples taken from several different spots. However, the beds have been amended yearly with compost, lots of it, so I would have thought that the ph would have gone down if anything. So, in answer to your question, really, it's time to do another test. Too alkaline for onions, yes?