Could problem compost have led to all my veg seed sowings failing?

betty morLey, by emaiL

AAlthough it’s possible that your compost was the problem, you bought a recognised brand and sowed a wide range of seeds, so it’s unlikely. The fact that you bought seeds from a variety of suppliers rules out seed problems too. The most likely problem was cold temperatures when the seeds were sown. Spring was very cold and wet and even in a greenhouse low temperatures could have led to seeds rotting rather than germinating.