greenhouse germination

[charles]

 Yes but most leaves in winter are created on older plants with established root systems. New seedlings need time and energy (the warmth you give them included) to reach a stage where they can offer worthwhile harvests. So it is best to have sown in September, then pick leaves carefully off these plants all winter. Any extra warmth for existing plants will certainly result in more leaves, but I do emphasise that in mild weather there should be a reasonable number of small new leaves on indoor, unheated plants.