I recently picked up a soil pH meter and took a series of readings
across my garden. Most of my results were in the 6.0 to 6.8 range,
but I do have one corner of my garden where the pH ranges from 5.2 to
5.9. I added some slow release, pellitized lime, but I understand
that can take up to 6 months to dissolve and change the pH. I have
onions, tomatos, peas, beans and radishes planted in this area. 2
questions, how bad is a 5.2 pH on these plants and should I perhaps
carefully sprinkle some quick lime on the surface and incorporate
this? My rows are spaced at 18" so I should be able to do this
without touching any plants. Or would this cause a too radical pH
swing and am I better off suffering with the present pH until it
slowly adjusts?

Assuming your pH meter is some where near accurate, I would just stick with the
pellatized lime. The more acid the soil the faster it works. The peas and beans
are not happy at that pH but tomatos are relatively tolerant.