Signs that soil pH needs adjustment

[Tomhanks]

What are common signs that soil pH levels may need adjustment?

[davidlaid]

You might notice signs like yellowing of leaves (especially between veins), stunted or slow growth, purpling or red-tinged foliage, leaf curling or distortion, or browning and tip die-back — all often caused by nutrient lock-up or toxicity when soil pH is too high or too low.

[Tomhanks]

Thanks for the reply! Can soil pH be tested at home?