Plants can either be propagated by division or raised from seed or, in the case of some species, by both. Division is best done in spring at the first signs of growth.
A suitable sowing medium for seed is two parts multipurpose peat-free compost to one part perlite, passed through a sieve. Meconopsis seed requires light to germinate so either surface sow and cover with a thin layer of vermiculite to anchor seeds and prevent drying out or, alternatively, top off the pot with damp perlite and sow the seed into this.
Meconopsis seed has short term viability. Late summer and autumn sowing gives best germination in about three weeks but seedlings then need to be overwintered in a cold frame or similar. Sowing in February allows a full growing season for the young plants to develop unchecked but it is important to store the seed overwinter in cool, dry conditions in the bottom of a domestic refrigerator.
As pot-grown seedlings develop the first pair of true leaves they should be pricked off into containers of a similar medium to that detailed above. Many seedlings are lost when pricking out. To avoid this sow a tiny pinch of 3-5 seeds into each module of a plug tray. Once plants have germinated they can be potted on in a group without any disturbance.
Seedlings need careful watering as excessive wetness or dry conditions can both be fatal. Transplanted seedlings should be fed with a weak liquid feed every fortnight during the growing season. A covering of horticultural fleece will reduce transpiration and the possibility of scorch from bright sun and will also protect against frost.
Pot on regularly as the seedlings develop to avoid a check in their growth and plant out in the autumn or the following spring.