Where do I source iceberg lettuce seed and which variety heads well?

Iceberg lettuce is grown from hybrid or improved variety seed sold by private vegetable seed companies, usually imported genetics, bought through authorised dealers or reputable agri seed sellers; keep the bill and tag. Choose a variety known for firm heading and bolt tolerance in your climate, because heading ability varies a lot between varieties. Seed is small and is usually raised in trays before transplanting. Since buyers like QSR chains often specify a variety or head type, confirm with your buyer and your KVK which variety has performed locally before buying in bulk.