Papaver rhoeas, commonly known as the corn poppy, is an annual herbaceous plant that’s either completely covered with protruding bristles or rarely hairless. It has a straight stem that stands 25-90 centimeters tall with branches.
The leaves are lanceolate or narrowly ovate in outline, featuring pinnate divisions. The solitary flowers bloom at the tops of the stems and branches, the buds being long, ovate, and pendulous. The plant bears two broadly elliptical sepals and four petals which can be round, transversely broadly elliptical, or broadly ovate in shape, spanning 2.5-4.5 centimeters.
The petals, predominantly purple-red and often featuring deep purple spots at the base, are typically entire, seldom round-toothed, or apically notched.
The fruit of this plant is a broadly ovate capsule, 1-2.2 centimeters long, hairless, with indistinct ribs. The seeds are numerous, kidney-shaped to elliptical, and about 1 millimeter long. Flowering and fruiting occur from March to August.
Native to Europe, it is widely cultivated throughout China and known for its ornamental value. Both the flowers and the whole plant are used medicinally, containing various alkaloids with cough-suppressing, anti-diarrheal, analgesic, and sedative effects. The seeds contain over 40% oil content.
Morphological Characteristics
The Papaver rhoeas is an annual herbaceous plant that’s usually covered with protruding bristles or occasionally hairless.
The stem stands upright, ranging from 25-90 centimeters in height, with branches, and is covered in pale yellow bristles. The leaves are alternate, lanceolate or narrowly ovate in outline, 3-15 centimeters long and 1-6 centimeters wide, with pinnate divisions.
The lower leaves are fully divided, with the segments lanceolate and secondarily shallowly divided. The upper leaves are deeply or shallowly divided, the segments lanceolate, with the uppermost parts coarsely toothed and shallowly divided. The apical segments are usually larger and the smaller ones taper towards the tip.
Both surfaces of the leaf are covered with pale yellow bristles, the veins being prominent on the underside and slightly depressed on the surface. Lower leaves possess petioles, while upper leaves are petiolate.
The flowers bloom singly at the tops of the stems and branches. The pedicel is 10-15 centimeters long and is covered with pale yellow, spreading bristles. The buds are elongate, ovate, and pendulous. The sepals are two in number, broadly elliptical and 1-1.8 centimeters long, green, and covered with bristles on the outside.
The petals are four, either round, transversely broadly elliptical, or broadly ovate, 2.5-4.5 centimeters long, entirely margined, seldom round-toothed, or apically notched. The petals are purple-red, usually with deep purple spots at the base.
The stamens are numerous, the filaments are thread-like and about 8 millimeters long, deep purple-red. The anthers are elliptical and about 1 millimeter long, yellow. The ovary is ovate, 7-10 millimeters long, hairless. The styles are 5-18 in number, radiating, united into a flat disc with a round-toothed margin.
The capsule fruit is broadly ovate, 1-2.2 centimeters long, hairless, with indistinct ribs. The seeds are numerous, kidney-shaped to elliptical, and about 1 millimeter long. The plant flowers and bears fruit from March to August.
Growth Environment
The Papaver rhoeas thrives in temperatures ranging from 5 to 25°C, with large day-night temperature variations and cooler nights promoting better growth and blooming. It flourishes in high-altitude regions, exhibiting brighter colors.
Its typical lifespan is 3-5 years. Resistant to cold but susceptible to heat, it prefers ample sunlight and well-drained, fertile sandy loam soils. It does not tolerate transplanting well, nor waterlogging, and should not be consecutively cropped. The Papaver rhoeas readily self-sows. Its flowering period is from May to August.
Distribution Range
Originally from Europe, the Papaver rhoeas is commonly cultivated all over the world and throughout China as an ornamental plant.
Growth and Propagation
The Papaver rhoeas is primarily propagated by seeds and is usually grown as a biennial. The Papaver rhoeas and other plants in its genus have a taproot system, few fibrous roots, and do not tolerate transplanting well. Therefore, it is best to use direct seeding for propagation.
If it is needed for landscape decoration, it’s advisable to germinate the seeds in nutritional pots or small paper pots, and transplant them along with the pots to avoid damaging the root system and causing poor growth or plant death.
The sowing season is determined by the local climate. In the colder northeast regions, early spring sowing is preferable. As the seeds are tiny, precision sowing in rows, with a spacing of 25-30 cm, is needed.
To prevent the seedlings from freezing, they can be covered with dry straw in severe winters. The optimal temperature for seed germination is 20°C. Seeds can be sown directly in pots for home gardening.
Seed propagation is done in both spring and fall. Normally, spring sowing takes place in March or April, with a flowering period of June to July, while fall sowing occurs from September to November, leading to flowering in the following May to June.
Fall sowing is preferred for seed collection. The soil should be well-prepared and moist before sowing, which can be done by broadcasting or row sowing.
As Papaver rhoeas seeds are tiny, it is essential to ensure that the soil is leveled and finely tilled. After broadcasting, the seeds do not necessarily need to be covered with soil, but a thin layer of fine sandy soil can be used.
The cover soil thickness should be such that the seeds are just barely visible (0.2-0.3 cm). In northern China, where winter conditions are harsh and seedlings struggle to survive, sowing is usually done in early winter during light snowfalls to ensure early sprouting and growth in spring.
Cultivation Techniques
Site Selection
The Papaver rhoeas prefers a sunny, well-ventilated location; it can withstand cold but not wet or hot conditions. It should not be planted in overly fertile soil, nor consecutively cropped. Avoid water-logged, damp, over-fertilized, or poorly lit areas for seedling growth and planting, as these conditions can lead to poor growth and increase the risk of diseases.
The plant isn’t particularly picky about soil but performs best in loose, fertile sandy loam. Plant rows should be spaced 20 cm apart. After sowing, cover with a plastic mulch, or sow seeds as soon as the soil thaws in early spring, gradually removing the mulch after the seedlings emerge.
Pot Planting
In January, use a 20-cm-diameter pot filled with loose old potting soil. Flatten the soil, sow 20 to 30 seeds, and cover them with just enough soil to hide the seeds. After sowing, soak the pot in water. Once the seedlings emerge, thin them several times, keeping the robust seedlings and removing the weak ones, leaving 3 to 5 plants.
When the seedlings reach a height of 30 cm, gradually fill the pot with potting soil up to the rim to prevent the stems from becoming thin and falling over.
Maintain ample light and fresh air environment, ensure the temperature doesn’t drop below 5°C at night, and avoid drought and waterlogging. The Papaver rhoeas should start blooming in March and continue until May Day.
Thinning
Common poppy, or Papaver rhoeas, is typically cultivated as a biennial. When seedlings develop 5-6 leaves, thin them out to a spacing of roughly 30×30 centimeters. Poppy plants don’t tolerate transplanting well, so direct sowing in the garden is recommended.
Fertilizing
Apply a dilute liquid fertilizer 2-3 times before flowering, but be careful not to over-fertilize, as this can lead to disease and pests. When planting in the ground, apply a light fertilizer twice before winter, then apply a liquid fertilizer before flowering. Finally, a top-dressing fertilizer should be applied one last time before flowering to encourage large, vibrant blooms.
Watering
During the seedling growth phase, avoid excessive watering while keeping the soil moist. In general, ground-planted poppies don’t require frequent watering, whereas potted plants may need watering every 3-5 days, depending on the weather and soil conditions.
Maintaining soil moisture at about 60% of field capacity is optimal for poppy development. Water less during winter and increase watering as growth picks up in the spring.
Management
Maintain a temperature of about 20°C after transplanting and buds will appear within 7-10 days. Infected plants should be treated promptly, and field sanitation should be observed. Avoid damp, hot nursery grounds or poor ventilation. Rotation cropping is recommended.
Pruning spent flowers can extend the blooming period and result in larger and more beautiful blooms. The seeds mature uniformly, which allows for a single harvest.
Pest and Disease Control
Common diseases include wilt during the seedling stage, which can be sprayed with a 1000-fold dilution of 25% Thiram wettable powder. After the seedlings have sprouted, use a 1000-fold dilution of Carbendazim or Methamidophos every week for 2-3 consecutive times.
Common pests include aphids, which cluster on tender shoots and suck sap from the leaves. They can be controlled using various diluted insecticides such as 35% Nicotine sulfate, 2.5% Imidacloprid, 50% Aphid killer, 10% Lambda-cyhalothrin, 2.5% Kung Fu, 40% Propargite, 40% Parathion, and 2.5% Rotenone.
Main Values
Ornamental
Papaver rhoeas, commonly known as the poppy, boasts vibrant and abundant blooms. Its thin, smooth petals sway effortlessly, resembling floating silk ribbons in the wind. The flowers are aesthetically pleasing and have a long blooming period, making them suitable for flower beds, gardens, pots, or as cut flowers. Planted en masse in parks, they create a delightful landscape.
Since each plant has many buds, the blooming period is extended. If used as cut flowers, they should be cut at half bloom and immediately placed in warm water to prevent excessive sap loss, which would cause the stems to wilt and the flowers to not fully open.
Medicinal
The whole plant (poppy), flowers, and fruits are bitter and astringent with cooling properties. They have analgesic, antitussive, and antidiarrheal effects, and are used for coughs, dysentery, and abdominal pain.
Both the flowers and the whole plant are used in medicine and contain a variety of alkaloids, providing cough suppressant, antidiarrheal, analgesic, and sedative effects. The seeds contain over 40% oil.
Plant Culture
Legend
Legend has it that at the end of China’s Qin Dynasty, during the conflict between Chu and Han, Xiang Yu, the overlord of Western Chu, was defeated and surrounded by the Han army at the Battle of Gaixia.
Knowing he was trapped, he spent the night drinking with his favorite concubine, Yu Ji. Suddenly, the sounds of Chu songs filled the air, and he could not help but lament with sorrow: “With strength to pull up mountains, and spirit to overshadow the world, yet time is not on our side, and our horses are not advancing. What is to be done? Yu Ji, what is to be done?”
Yu Ji, sensing the impending doom, began to dance with tears in her eyes and sang the “Song of Gaixia”: “Han soldiers have taken our land, Chu songs resound in all directions, the great king’s spirit is exhausted, why should I, a lowly concubine, continue to live?”
After the song, she pulled a sword from Xiang Yu’s belt, and with one swift movement, cut her throat, dying in a stream of blood. This story, known as “The Hegemon-King Bids His Concubine Farewell,” is one of the most tragic and poignant love stories of the Warring States period. It has been told and retold for hundreds of years, always leaving its listeners deeply moved.
Later, a type of grass grew on Yu Ji’s grave. It resembled cockscomb, with opposite leaves, long and soft stems, and a movement as if dancing even in the absence of wind, charming and lovely.
According to folklore, this was the manifestation of Yu Ji’s pure spirit. This grass was named “Yu Beauty Grass,” and its flowers “Yu Beauty.” The bright red of the Yu Beauty flowers is said to have been dyed by the splashing blood of Yu Ji.
It’s as if Yu Ji lives on after her death, transformed into the Yu Beauty Grass. It blooms every year from late spring to early summer, even as a perennial, continuing to symbolize her unwavering loyalty and waiting for the overlord. It continues to laugh and dance for the overlord all year round, just as it did in the past.
Peggie was once a high school mathematics teacher, but she set aside her chalkboard and textbooks to follow her lifelong passion for flowers. After years of dedication and learning, she not only established a thriving flower shop but also founded this blog, “Flowers Library”. Here, Peggie shares the art and science of floristry, offers practical tips for nurturing plants, delves into the captivating histories of various species, and provides insights into running a successful flower shop. She hopes that everyone can take a moment now and then to immerse themselves in the world of flowers. If you have any questions or wish to learn more about flowers, feel free to contact Peggie.
