Lime sulphur blocks spray nozzles.

wine-o-clock, Jul 3, 7:25pm
I made some up a few days ago, went back to continue today and the silly stuff won't pump out! How can this be avoided please?

maclad, Jul 3, 11:17pm
By emptying the sprayer and flushing the line with clean water

ebygum1, Jul 4, 3:30pm
By keeping it clean.

grassman, Nov 30, 1:15pm
Never leave Lime sulphur in sprayer any longer than you need too. If the spray wand is metal or aluminium it will react and stick in it forever. No amount of water will clear it if it has gone hard in the wand. You could try to push a length of thin wire through the wand to try and clear it.