Meconopsis seeds need to be fresh.(store in 'frig)
They will sprout readily at about 60ยบ F .
They like a peaty moist, but not wet soil.
I can get them to sprout,but have not been able to carry them through to the garden.
One needs to water with peroxide in the water to avoid molds which cause damp off.
Last year I did get seedlings transplanted to garden, but then there was a big rain and they were damaged.
They need protection from slugs too.