soil prep

welcome to Goy :o)

The Rhs advice about lime is very helpful. The link below will address lots of questions about lime and liming.

https://www.rhs.org.uk/advice/profile?PID=144

Not meaning to sound glib but isn't the answer 'When it needs it'? If you know for sure acidity is up then add lime, if you're unsure then maybe hold off till you've checked?

it takes time for the lime to 'react' to alter the soil pH so it may be that it needs to be on for a while before you plant in it Darren. Certainly farmers here add it late autumn/winter ready for the crop they need to grow. Though it depends on which crop they are growing.

Unless your soil is pretty acid you might just add some when planting brassicas. An old allotment gardener taught me to dip the roots in lime before planting. Hard to believe but it was OK. Have you done a pH test on your soil?