Liquid Black Crystal 4 litre

Liquid Black Crystal assists in increasing the ion exchange across
the root membrane. It improves the plants ability to absorb nutrients.
Liquid Black Crystal must be put into your reservoir or used as a soil
drench. It is most effective when it is applied to the root zone of a
plant. DO NOT foliar spray with Liquid Black Crystal. Can be used
for gardens and lawns, particularly where the pH of the soil is high.