Hi all, I just did a soil test on my newly created veggie beds.

Here is the result:
Alkalinity: pH 8.0
Nitrogen: sufficient to slightly surplus
Potash: deficient

....and then there was the Phosphorous test which is the puzzling one! The
liquid was supposed to turn blue, to a greater or lesser degree, but it
didn't! It turned a very pale amber (the colour of the average lager or
cider). What does this indicate? Extreme phosphorous deficiency??

The test kit is called a "Mini Soil Test Kit", containing four vials, each
with a different clour cap, and two each of four different chemical (each
in a capsule, which you pull in two and add content to the liquid in the
vial).

I followed the instructions to the letter. My soil is somewhat clayey and
sandy and has had a fair bit of last years compost dug into it.

What is the cheapest way to add potash and phosphorous (assuming I need
it)?

Thank you,

Jake