Pepping the lawn for spring/summer

What do you use on your lawn to promote strong healthy growth in preparation for the months ahead? and when is the best time to do it please?

 

Nothing and never. My grass grows perfectly well without any stimulants to pep it up.

 

In the past I have just used blood fish and bone, scattered on the lawn in late Feb/early March. Over the last couple of years my lawn has been mossy due to all the winter wet and lack of sun so I have used a combination moss killer/fertiliser product, usually Miracle-Gro Complete 4 in 1. It helps but does not solve the moss problem totally due to my lawn being shaded and on sandy soil but it makes the lawn greener and improves the density of the grass.

 

Thank you @NigelJ and @Plantminded, unfortunately my lawn is looking very poorly, it is full of weeds and moss so it will need something doing.

 

I'd try a combination weed and feed product @Meomye then rake or scarify your lawn once the moss and weeds have died, followed by regular mowing, starting at a medium/high height, depending on how high your grass is, and then lowering it. A photo of your lawn would help with more specific advice.