When to Divide Poppies Divide poppies in late summer, once the plant has completely finished blooming. If you attempt to divide any earlier, you may kill the plant as poppies have sensitive root systems during growth. The day before division, water your poppies well to keep the soil intact.Click to see full answer. Similarly, it is asked, can poppies be transplanted?Oriental poppies (Papaver orientale)—the type with large, showy spring flowers—are best transplanted in late summer, when they are not actively growing. They have long tap roots that can make moving them a little challenging. Dig deep down to get under the tap root, then lift up carefully. Try not to break the roots.One may also ask, should poppies be deadheaded? Some poppies are annuals and other are perennials. If you’re happy with the numbers of flowers your poppies produce, it’s not necessary to deadhead them unless you want to keep them from spreading. If not deadheaded, California poppies spread widely and can reduce erosion. Similarly, you may ask, how do you propagate poppies? Lift a clump of the oriental poppy that you want to take cuttings from or just scrape away the soil around the roots. Trim off a good section of the roots with a knife. Cut the root into short lengths (around 2.5cm) and push these vertically into a seed tray, of compost, thick end up. Should I deadhead Iceland poppies?Deadhead Iceland poppy plants frequently to promote new blooms and stop the plant from spending energy to produce seed. Cut away flowers once they have dropped their petals or when their heads begin to hang downward.