I have a moisture meter that registers readings from 0.0 to 9.9 (driest to wettest). I cannot find a listing for a potted avocado tree. Can you give me info as to what percentage is optimal for the plant? I'm not that good at pressing on the soil and figuring it out from there.
Without knowing what meter you are using, and whether the readings are linear or not then, one would have to guess.
It's recommended that avocados be watered 3 time a week to simulate what happens in their native environment, and potted into a free draining soil. This is important as the roots can rot if submerged for a day. However the pot should not be allowed to dry out completely.
If the tree is potted into a sandy loam soil, then your meter should read towards the moist side eg. 8 but if in a loamy soil, then aim for near mid way eg. 6. The corresponding tensiometer readings are 20 cb and 40-45 cb where 0 cb is when the soil is saturated.