Papaver rhoeas. Sow heirloom Flanders poppy seeds for bright red summer colour in nearly any soil. Flanders poppies are quite drought tolerant, so they are useful in xeriscaping schemes. They self sow fairly reliably without ever becoming weedy. It's a good choice for any areas where grasses are allowed to grow tall in summer, with the poppies growing to around 60cm (24") tall. Gather the dried seed heads in late summer for decorative dried flower arrangements. Plants produce abundant tiny seeds that are very easy to gather and give as gifts. This species is mildly toxic to grazing animals, but its acrid taste puts most animals off anyway. So it is a very useful deer resistant variety that looks spectacular when planted in large areas.
These annual and perennial flowering plants have striking similarities, but a surprising range of colours and growth habits. It is easy to grow poppies from seeds. In the right setting, they grow and then self-sow with abandon, without becoming weedy. They will thrive for years at a time in surprising spots, like a crack in the driveway.
Papaver nudicaule (perennial), P. rhoeas & P. somniferum (both annual)
Season & Zone
Exposure: Full sun to partial shade
Zone: P. nudicaule is hardy to Zone 3
Start perennial poppies outdoors in early spring, when some chance of frost is still a possibility. Start annual varieties outdoors at the same time in Zones 3-7. In Zones 8-10, the best bet is to direct sow in the fall.
Poppies are famously difficult to transplant, so starting them indoors is not recommended. If absolutely necessary, use peat or coir pots, and maintain a soil temperature of 12°C (55°F). Seeds will sprout in 20-30 days.
Sow on the surface of the soil, or barely cover seeds. Thin to a minimum of 15cm (6″) apart.
Poppies are easy to grow and the self-sow with abandon, without becoming weedy. Simply pull up unwanted plants (an easy task) before they bloom, or better yet, let them tell you where they want to grow. They will thrive for years at a time in surprising spots, like a crack in the driveway. Other times, they simply won’t take, no matter how much you try. Keep them moderately well watered in hot, dry weather, and do not fertilize.
For the largest heads on Papaver somniferum, sow seeds in the fall or early winter. Thin plants to allow them some space, and keep the area weeded as plants grow larger. Grow this variety in full sun in well-drained, but ordinary garden soil. If spring and summer are cool and damp, or plants are over-crowded, expect smaller seed heads.