On 31/08/2019 09:39, Bert Coules wrote:
"Jim GM4DHJ ..." wrote:

And the right amount of washing up liquid ....

Would you add plasticiser (or washing up liquid) to shed-bought
ready-mixed mortar?Â* That's what I used on this latest effort, but with
nothing added.

yes. All you have bought is premixed sand and cement.