Continue with pool protection.
  Remove weeds from the bog garden; this task is often easiest after light, drying frost.
Sow primulas. Sow moisture-loving primulas, which germinate better after freezing. Fill seed boxes to within ¾ in. of the top with John Innes seed compost. Firm down with the fingers, especially at the corners and sides, and level off with a board. Sow the seeds thinly, then cover lightly with finely sifted compost. Water carefully, using a can fitted with a fine rose, or soak by standing the box in shallow water to within ½ in. of the soil surface. Stand the boxes outside on a level site in light shade and allow them to freeze, but protect them from heavy rain.
  Alternatively, put sown boxes inside polythene boxes and seal the ends until germination takes place.