Rapitest soil test kit

[SeaWalnut]

Ive just received this soil test kit.It measures NPK but the skale its with ,,sufficient ,adequate,deficient,, instead with numbers in ppm.I got this because i grow somme trees that need verry low phosphates.Any opinions about the test?

[SeaWalnut]

It seems that i cant find a chart with numbers in ppm to get an idea of what ,,sufficient,, means on this test.
Different plants have different needs and what is sufficient for somme plants could be defficient for otthers.So far,even by amateur standards this test doesnt look too good altough its cheap and its a good idea to test the soil for nutrients.