Clay soil is made up of very fine particles, which means that water and air cannot move easily through it. For this reason, it can be prone to waterlogging. For clay soil remember to keep off it when it’s wet, to avoid compaction.
Overtime you can improve the structure of clay soils by working in bulky organic matter like compost, leaf mould, grit or some well-rotted bark chips. Adding in a liming agent, like calcium, can also encourage the clay to clump and this makes it easier to work with.
Don’t forget, you can mound up the soil when you’re planting to prevent plants from sitting in water.