We attended a garden party last weekend. The hostess is a serious gardener. She had so many poppies in bloom and post-bloom that I told her that I should perhaps call the cops.
Poppies are best considered annuals, but they will self-sow if left alone. In parts of Europe, red poppies are considered roadside weeds. In our wild (no horses) meadow I strewed (?) poppy seeds around many years ago, and many of them took. Now the meadow in June has some naturalized poppies amongst the wildflowers and hay.
Varieties of garden poppies
Planting and gowing poppies