There is a kind of flower with white flowers outside and red flowers inside. What kind of flower is this? [with pictures]

Introduction Longtuzhu, also known as Pearl Lotus, is a plant of Erythrina in Verbenaceae. In summer and autumn, the terminal white calyx spits out a bright red corolla and is embedded in red and white. It's beautiful. It's a common potted flower.

Longtuzhu is native to tropical West Africa. Introduced to Britain from 65438 to 0790, it is mainly used for greenhouse cultivation and appreciation, and is widely cultivated in European botanical gardens. At present, Europe and America use dragon spit beads as potted plants to decorate windowsills and small courtyards in summer. So far, Goya Nursery in Israel and Aosi Pacific Plant Company in Australia have started industrial production and supplied to the international market.

Longtu bamboo has not been cultivated in China for a long time. In Guangzhou in the south in the early 20th century. Xiamen and other cities are cultivated. After the founding of New China, greenhouse cultivation was introduced into botanical gardens around the country. At present, it has been mass-produced in Shenzhen, Guangzhou, Zhuhai and other cities. Potted dragon spit beads can be seen in flower markets all over the country, and they have begun to enter family potted plants for viewing.

Morphological characteristics and varieties Longtu bamboo is a climbing evergreen shrub. Leaves opposite, ovate, pointed, entire, lateral veins obvious. Flowers clustered, terminal or axillary. The calyx is white first and then pink, forming a pentagonal shape, the top gradually narrows, the petals are red, the stamens are long and protrude outside the corolla. Its cultivar Variegatum has dark green leaves and irregular white stripes.

The common ornamental species in the same genus is water lily, with a plant height of 60 cm and bright red flowers. God of Wealth, with white flowers and black fruits. Smith has dark green leaves and bright red flowers. C. fragrans, a dwarf plant with double pink flowers. Creeping shrub with white flowers. C. japonicum is a shrub with heart-shaped leaves, bright red flowers and blue-black fruits. C. Myrica rubra, a shrub with blue-purple flowers. Zhu Dinghong has red flowers, pale pink sepals and white styles. C.splendens with bright red flowers. C. wallichii is an evergreen shrub with dark green leaves, red sepals and white flowers.

Biological characteristics Longtuzhu is native to western tropical Africa. Like warm, humid and sunny environment, not cold-resistant.

The optimum growth temperature of Dendrocalamus latiflorus is 18 ~ 24℃, 18 ~ 30℃ from February to June, and 13 ~ 16℃ from June to February. In winter, the temperature is not lower than 8℃, and the stems and leaves above 5℃ are vulnerable to freezing injury, and the leaves fall lightly and wither severely. In the vegetative growth period, the temperature can be higher than 30℃, and it can still grow normally as long as the water supply is sufficient. The temperature of reproductive growth, that is, flowering period, should be low, about 65438 07℃.

Dragon spit beads are very sensitive to water. In the stem and leaf growth period, the saline soil should be kept moist, but it is not advisable to water it too much, so that only long vines will not bloom, and even the leaves will yellow and wither, and the roots will rot and die. In the hot summer season, it is necessary to fully water and shade properly. In winter, water should be reduced to make it dormant, so that it can be safely wintered.

Longtu bamboo needs plenty of light in winter, and it needs shade in summer when it is too hot, otherwise the leaves will turn yellow. Insufficient light will cause vines to grow and not bloom. Flower bud differentiation is not affected by photoperiod, but strong light can promote flower bud differentiation and development. It should not be kept in the dark for too long. If the temperature is above 2 1℃, it will fall out after more than 24 hours.

Sandy loam with fertile, loose and well-drained soil. Culture soil for potted plants or mixed soil of peat soil and coarse sand.

Commonly used propagation methods include cutting, dividing plants, sowing and so on.

Cutting propagation: Common cuttings, bud cuttings and root cutting. The top branches of healthy and disease-free branches can be selected, or the old branches at the lower part can be cut into stem segments of 8 ~ 10 cm as cuttings. Bud grafting is to take lateral buds from branches and take part of xylem as cuttings. Root cutting is to cut the rhizome stolon into 8 ~ 10 cm long for cutting. Substrates such as peat, perlite, humus, river sand and vermiculite can be used for bed insertion, and cutting in spring and autumn is the best. The suitable cutting temperature is 265438 0℃, and the transplanting temperature is 26℃, which is very beneficial to rooting. Rooting can occur after 3 weeks. If the base of cuttings is treated with 0.5% ~ 0.8% IBA solution for 1 ~ 2 seconds, the rooting can be faster and more.

Propagation by ramets: after flowering, dig new branches sprouting on underground stolons, directly plant them in pots by roots, and keep them in the shade.

Sowing and breeding: March-April. The seeds are large and germinate continuously for about 10 days after indoor potted planting at room temperature of 24℃. When the seedling height is 10 cm, it will be transplanted into a small pot for maintenance, and it will bloom in the next year.

Cultivation and management of potted Dendrocalamus latiflorus commonly used 12 ~ 15 cm pots, each pot can be planted with 3 plants. Adequate water is needed in the growing season. If the soil humidity is too high, the leaves will turn yellow and fall off. If the branches are not withered, stop watering and let them recover and grow new leaves. Fertilize every half month 1 time. Add 1 ~ 2 times phosphorus and potassium fertilizer at the flowering stage of Longtu bamboo, or use "Huiyou" potassium nitrate for 20-8-20 seasons. Reduce watering and stop fertilizing in winter. In order to shape the beautiful plant type of Dendrocalamus latiflorus, when the cuttings or seedlings grow to 15 cm after potted, the branches are cut off at the distance of 10 cm from the mouth of the pot to promote the germination of strong new branches. During the growth period, the height of branches should be strictly controlled, and topping and coring should be paid attention to, so that the branches will be neat and densely flowered in the future. Half a month after coring, apply Bijiu or Chlormequat chloride to control plant height, so as to achieve short plants, luxuriant leaves and many flowers. When changing pots in spring every year, the branches above the ground should be trimmed and shortened to make the plants round, with more branches and more flowers.

Pests and diseases control common rust, gray mold and mosaic virus diseases. The rust was sprayed 400 times with 20% Wei Xiuling EC, and the gray mold and mosaic virus disease were sprayed 2500 times with 50% Benomyl WP. Insect pests do great harm to leaf beetles, moths and scale insects, and 2.5% dichlorvos can be sprayed 3000 times.

Postpartum treatment Longtu bamboo leaves are dark green, calyx is jade, corolla is deep red and poetic. Potted plants adorn windowsills or balconies, which are beautiful and distinctive. During storage and transportation, flowers are sensitive to ethylene, and 0.4 mmol/L silver thiosulfate solution is sprayed before storage and transportation 10 day. Flowering plants without spraying silver thiosulfate are transported in the dark for more than 1 day, and the flowers fall off at 20℃.