April
Continue to increase the frequency of mowing throughout the month. Scarification will be increased to remove all the surface debris within the base of the sward. Rolling should be continued to provide a solid base for the playing season.
Additional rolling will be carried out for pitch preparation, however, the fundamental groundwork for the season is carried out prior to the first ball being delivered. Make sure the square is properly 'squared up' with the correct number of wickets being spot marked at the ends. Ensure each wicket is correctly squared.
A spring fertiliser will probably be applied this month, although be careful not to apply too much Nitrogen as the aim is to ensure strong root development and not excessive leaf growth.
May
Scarification of the square and during wicket preparation is an important operation for reducing undesirable thatch and this will help to improve bounce and pace, although wickets will probably still be on the slow side at present as the ground won't have been able to dry out adequately yet.
Wicket preparation will be occurring some 7 to 10 days before a game, with this time period going up to 14 days for top-class cricket.
A spring, mainly nitrogen, fertiliser should have been applied to the square, however, beware of leaching due to the wet weather as this may reduce the anticipated time for the next application.
Early use of the outfield should provide feedback of any slight depressions which may need attention to maintain an even and safe playing surface. Aeration of the outfield can also be considered, before the soil dries out too much.
Scarification, to reduce and control undesirable thatch build-up, is also ideally undertaken now. A light fertiliser (low in nitrogen) application for the outfield can also be given, if needed, especially after any aeration and scarification work.
The end of May is also usually a good time to apply a selective herbicide to the outfield.