Before removing this poppy from its nursery container, water it well. The moist soil will clump together and help prevent damage to the plant’s root ball—which should not be broken apart during planting. Even though this is a drought-tolerant perennial, water it thoroughly after planting and continue watering weekly throughout the first growing season. Once this poppy is established, you may not need to water it ever again. Matilija poppy commonly goes dormant in the heat of summer or in fall. Cut it back to a 3- or 4-inch stalk at that time, knowing the poppy will reappear in spring. Be patient; Matilija poppy is tricky to get started because it doesn’t like being transplanted or grown from seed. Once established, though, watch out! It will spread quickly by underground rhizomes and can invade distant areas of the landscape—which means it’s not a good choice for small yards or containers. Prevent Matilija poppy from creeping into other areas by installing a root barrier at planting time. This solution can be as simple as planting it in a pot that is sunk into the ground. Situate the pot so the edge of the container is about 2 inches above the surrounding grade to prevent it from growing out of the pot and into nearby soil. Smaller plants cannot compete with Matilija poppy plants, which may reach up to 8 feet tall. Partner the poppies with shrubs that can compete for available sun. Consider California lilac (Ceanothus), sugar bush (Rhus ovata), coffeeberry (Rhamnus californica), or flannel bush (Fremontodendron).
