Detailed Guide to Corn Poppy Planting Methods and Technical Points

The corn poppy is mainly propagated by sowing, usually grown as a biennial. The corn poppy flower and plants of the same genus all have a taproot system with very few fibrous roots and are not tolerant of transplanting, so direct sowing propagation should be used. If needed for garden landscaping, it is best to raise seedlings in nutrient pots or small paper pots and transplant together with the pot, otherwise it is very difficult to survive or grows poorly. The sowing period is determined according to climate characteristics; the Northeast region is relatively cold, so sowing can be done as early as possible in spring when the seeds begin to germinate. The seeds are tiny, so sowing must be done carefully, using furrow sowing with a row spacing of 25-30 cm; in severe winter, cover the surface with dry grass to protect against the cold. The suitable temperature for seed germination is 20°C. At home, seeds can be sown directly in flower pots. 

Sowing propagation. Sowing can be done in both spring and autumn. Generally, spring sowing is in March-April, with the flowering period in June-July; autumn sowing is in September-November, with the flowering period in May-June of the following year. If the purpose is to collect seeds, it is best to use autumn sowing. The soil should be finely prepared, and the seedbed should be made and watered thoroughly, then broadcast or furrow sown. Because the corn poppy seeds are tiny, when sowing, the soil should be leveled and finely broken up; after broadcasting, there is no need to cover with soil, or a thin layer of fine sandy soil can be spread over them. The covering soil thickness should be such that the seeds are no longer visible (0.2-0.3 cm). In North China, because the winter is severely cold, seedlings find it difficult to overwinter, so direct sowing is often done at the time of "Light Snow" in early winter, which allows them to germinate and grow as early as possible in spring. 

Site selection: Prefers a place with ample light and good ventilation; cold-tolerant, not tolerant of moisture or heat, not suitable for planting in overly fertile soil, and not suitable for continuous cropping. Not suitable for raising seedlings and planting in low-lying, damp places with heavy water and fertilizer and poor light; otherwise growth is poor and diseases are likely to occur. It has no strict requirements for soil, but loose, fertile sandy loam is best, with a row spacing of 20 cm; after sowing, cover with plastic film, or sow in early spring when the surface just thaws, and gradually remove the plastic film after the seedlings emerge.

Pot cultivation: In January, use a flower pot with an inner diameter of 20 cm, fill it more than half full with loose old potting soil, press flat, sow 20 to 30 seeds, cover with soil just until the seeds are no longer visible, and after sowing, soak the pot in water to moisten it. Once the seedlings emerge, thin them out several times, removing the weak and keeping the strong, and finally keep 3 to 5 plants for final planting. When the seedlings are 30 cm tall, gradually fill in planting soil up to the rim to prevent the thin stems from lodging. Keep sufficient light, fresh ambient air, night temperature not lower than 5°C, avoid drought and waterlogging; it can bloom in March and continue until "May Day."

Thinning: The corn poppy is usually grown as a biennial. When the seedlings have 5-6 leaves, thin them out, with a plant and row spacing generally of 30×30 cm. The corn poppy is not tolerant of transplanting, so direct sowing in the garden is best.

Fertilization: Apply 2-3 times of thin liquid fertilizer before flowering, but do not apply too much fertilizer, otherwise pests and diseases are likely to occur. For field planting, apply thin fertilizer twice before overwintering, and apply liquid fertilizer once more before flowering. Apply one final topdressing before flowering to promote large, brightly colored flowers and vigorous blooming.

Watering: During the seedling growth period, do not water too much, but keep the soil moist. For field planting, generally there is no need to water frequently; for pot cultivation, water once every 3~5 days depending on the weather and potting soil conditions; about 60% of the field soil's maximum water-holding capacity is better for the development of the corn poppy. Water less during overwintering, and water more during spring growth.

Management: After transplanting, maintain a temperature of around 20°C, and buds will appear in 7-10 days. If diseased plants are found, treat them promptly and pay attention to field sanitation. Do not let the nursery land be hot and humid or poorly ventilated. Avoid continuous cropping. If the withered stems that have already flowered are cut off in time, the flowering period can be extended and the flowers will be larger and more beautiful. The seeds mature uniformly, so they can be harvested all at once.