mmmm depends on the type of plants and when they start growing.wait till spring the plant the seeds(may i make a suggestion;poppies will look nice as well as buttercups and daisies :)

Just wondering why camassia - if the meadow is in UK why not have native flowers? Bluebells and/or cranesebill would be nice and the same colour..I have no idea how camassia would take to naturalising in a British meadow. Bluebells and allium also flower together., but they are both basically woodland plants, though they will grow in the open. Bluebells you would plant in the autumn and if you decide to go for them make sure you get the native English and not the Spanish.