Charles/Leif
My experience with germinating leeks this year has been this: the ‘MPC’ from a local garden centre was rather woody and the plants germinated OK indoors in a deep rectangular container. However, they struggled the first 4 – 5 weeks after appearing and benefitted very greatly from two seaweed liquid feeds about 3 weeks apart.
Now, however, the past 3 weeks they have really thrived and shot on and are looking perfect as they become ready to transplant.
As leeks need 8 – 10 weeks prior to transplantation, it may be that balancing optimum food for germination and for growing on may need to be balanced with external food supplements, unless you happen to hit on a great MPC for leeks.