Cultivation of African impatiens

African impatiens are widely used and can be planted on a large scale in nutrition bowls, pots and hanging baskets. At present, the main varieties of African impatiens on the market are 'stress', 'Victoria Rose', 'Jedi Storm', 'somersault Cloud' and so on.

The initial time of flowering flower bud differentiation was 12 to 14 days after sowing, and the second to 4 leaves grew out.

The flowering habit of African impatiens is a solar plant, and flowering has nothing to do with the length of the day.

The flowering mechanism had nothing to do with light intensity, but early flowering was induced by drought stress.

The optimal conditions for seedling development are below the germination stage of hole culture, which is from the beginning of seed sowing to the end of cotyledon development. The radicle is expected to grow from 2 to 5 days after sowing.

The seeds need to be covered with a thin layer of medium-sized vermiculite to moisturize. When the pH value of the substrate is from 6.2 to 6.5, when the pH value is less than 5.5, it will lead to terminal bud damage and sodium poisoning, and the EC value is 0.5 to 0.75. Seed germination needs light, such as dark room culture, need to be given light intensity of 100 lux to 1000 lux, to ensure germination and reduce overgrowth. The water content was maintained at level 5 until the radicle was emitted; from 3 to 7 days after sowing, the water content was reduced to level 4; from 8 to 10 days, it was reduced to level 3; after 11 days, the water content was reduced to level 2 until the cotyledons unfolded (water content: 0% to 20%, grade 2, 20% to 40%, grade 3, 40 to 60%, grade 4, 60 to 80%, grade 5, 80 to 100%). Do not let the leaves of the seedlings remain moist overnight, or it will lead to abortion at the top of the plant. Keep the air humidity at 100% until the radicle grows; then the humidity is reduced to 40% to 70%. Strengthen ventilation, make the matrix moisture evaporate and become dry, and ensure the root ventilation. When the temperature is maintained between 22 ℃ and 24 ℃, when the temperature is more than 25 ℃, it will cause heat shock and inhibit its germination; below 21 ℃, it will reduce the speed and consistency of impatiens germination; when it is lower than 18 ℃, it will cause plant tip abortion and leaf deformity.

The optimal condition of seedling vegetative growth period is below full hole / flower bud differentiation stage, which begins from cotyledon development. At this stage, the root system of the plant will expand to the edge of the hole, and the plant has completed the preparation of flower bud differentiation.

The pH value of the culture medium was 6.2 to 6.5, and the EC value was 0.75. If it was greater than 1.25, it would lead to plant tip abortion. The total EC value of water and fertilizer should not exceed 1 to avoid leaf deformation. Provide 25000 lux of light. In areas with low light levels, supplementary light of 3500 to 4500 lux for two weeks could promote the sturdiness and vitality of seedling rhizomes. However, in the early stage of hole culture, if light is provided for more than two weeks, it will lead to discoloration or yellowing of seedling leaves (photooxidation). Keep the temperature from 18 ℃ to 20 ℃ until the first true leaf is formed, then lower the temperature to 16 ℃ to 18 ℃ to increase color. Alternate water content, make it between grade 4 and grade 2, that is, first let the water content of the culture medium reach the level of level 2, and then increase to the level of level 4. The humidity is maintained at 40% to 50%. From the 2nd to 9th day of this stage, the concentration of calcium fertilizer from 25ppm to 50ppm (the ratio of nitrogen, phosphorus and potassium is 14-0-14, the same below), and then apply 75ppm to 100ppm fertilizer containing potassium and calcium for 2 to 4 times. Controlling the amount of fertilizer application can keep the seedlings compact and promote plant flowering. Avoid the application of phosphate fertilizer, otherwise it will lead to the excessive growth of African impatiens seedlings, while the addition of phosphoric acid to irrigation water will affect the quality of seedlings.

African impatiens can use growth regulators such as long-term, paclobutrazol or uniconazole, but excessive use of growth regulators can cause inverted cup-shaped deformities or distortions in immature leaves. Plant growth can also be controlled by adjusting water, light and fertilizer. Compared with other varieties, Jedi Storm has different tolerance to plant growth regulators, so it is recommended to use plant growth regulators in the hole culture period; in the later stage, plant growth can be controlled by the regulation of water and fertilizer. Under the conditions of high temperature and high humidity, the use of growth regulators can increase the color of the plant.

The preparation period for transplanting was 4 to 5 weeks after sowing in 288 plates.

The end of hole culture / flower bud differentiation stage is the optimal condition of vegetative growth period, this stage begins from transplanting, at this stage the plant root will expand to the edge of pot organ and flower bud differentiation will be carried out.

The pH value of the matrix is 6.2 to 6.5 and the EC value is 0.75 to 1. Shade is needed at this stage. The temperature ranges from 16 ℃ to 19 ℃ at night and from 21 ℃ to 24 ℃ during the day. The average daytime temperature is 19 ℃. Alternately adjust the water content so that it is between level 4 and level 2, that is, let the water content reach level 2 first, and then increase it to level 4. The humidity is kept between 40% and 70%. Strengthen ventilation, make the matrix moisture evaporate and become dry, and ensure the root ventilation. Apply 75ppm to 100ppm calcium fertilizer (13-2-13 or 14-4-14) for 2 to 3 times. Controlling the amount of fertilizer application can make plants grow closely and promote plant flowering; excessive fertilization can lead to too high plants, too many leaves, dark green leaves, delayed flowering or flowers under the leaves. The usage of plant production regulators is the same as above.

Post-harvest treatment period 1 to 2 weeks before picking or transportation.

The use of growth regulators is longer than the foliar spraying concentration of 2500 to 3000.

Potassium nitrate fertilizer with fertilizer concentration of 150ppm.

The most common diseases are Pythium root rot, Botrytis cinerea, tomato spot wilt virus, Alternaria leaf spot, Rhizoctonia solani, impatiens necrosis virus, pseudomonas bacterial disease and so on. Azoxystrobin is recommended to control gray mold and blight, metalaxyl can be used to control Pythium root rot, azoxystrobin can be used to control Alternaria leaf spot and blight.

Prone to insect pests are flies, thrips, aphids, red spiders and so on. It is recommended to use thiazine (indoor use, killing insects while cutting off the transmission vector of viral disease), spinosad (indoor use), miramine and other agents.

The Culture method of African Impatiens how to grow African Impatiens

African impatiens ranks first in the application of herbaceous flowers in Europe and the United States. It offers a wide range of bright colors and is thriving and easy to manage. Suitable for dish box container, hanging basket, flower wall, window box and balcony cultivation. With more than 90% germination rate in the seedling plate, impatiens has always performed better in all the quality parameters of the seedling plate than other varieties, with the earliest flowering, the most abundant color and free branching. The plant is covered with a large area of flowers, creating a first-class flower bed and flower belt landscape, with a height of 20-25 cm. Leaves and flowers are very colorful and colorful, with a total of more than 40 colors. Under the background of the shade of the garden, the color is harmonious, symmetrical and meticulous, enriching and increasing the tonal depth of the flowers.

Cultivation and management

Loose and fertile sandy loam should be selected for basin soil, for example, it is better to use peat soil or rotten leaf soil mixed with sandy loam soil and some rotten cake powder or chicken manure on the market. This kind of soil is loose and fertile, which is more suitable for plant growth and conducive to the root growth of young plants. The seedlings can be divided once at the 2-leaf stage and planted in the flowerpot when they are about 4 cm high. When planting, it is best to choose cold clips and wet environment to help slow the survival of seedlings and early flowering. After the planting survived, the heart can be removed once to promote lateral branches, which is beneficial to multi-branch and multi-flowering. The growth of seedlings is slow, but the seedlings can blossom. With the growth of seedlings, fertilizer and water management should be strengthened, dilute organic liquid fertilizer or 0.3% compound fertilizer can be applied once every 10 days. The flower likes to be warm, moist and avoid strong light. It is best to place it in a place where there is half a day or 70% light every day, and water is often sprayed around it, so as to keep the plant plump and the flowers blooming continuously. Great African impatiens like half-day light conditions, and have successfully bred sun-resistant varieties, such as the exhibition series can also grow well in full-day light, so they are also suitable for planting in flower beds.

African impatiens are suitable for planting on family balconies or windowsills or in the shade of courtyard trees because of their preference for semi-shade. There is degeneration in the flowering of the old plant, and the plant is not beautiful, so the new plant should be replaced by cutting and attention should be paid to pruning.

1. Planting: the seeds are usually sown from March to April in spring. It can be sown in the seedbed or directly in the courtyard flower bed. The seedlings grew fast and should be planted in the garden at the beginning of June after one transplant. If the sowing is postponed, the seedlings will be pots and can blossom on National Day.

2, light and temperature: like light, but also resistant to shade, to receive at least 4 hours of scattered sunlight every day. Shade should be carried out in summer to prevent excessive temperature and hot sun exposure. The suitable growth temperature is 16-26 ℃, and the ambient temperature at flowering stage should be controlled above 10 ℃. Enter the greenhouse in winter to prevent the cold.

3. Watering and fertilization: irrigation should be made in time after planting. Pay attention to watering during the growing period, often keep the basin soil moist, especially in summer, but do not accumulate water and the soil is too wet for a long time. If Rain Water should pay more attention to drainage and waterlogging, otherwise the roots and stems are easy to rot. Fertilization should be diligent after planting, and special attention should be paid not to dry or wet. Never water wilting plants in the hot sun in summer. Especially in the flowering period, do not suffer from drought, otherwise it is easy to fall flowers.

4. Florescence control: if you want to postpone the florescence, you can sow seeds in early July. The method of heart-picking can also be used to remove early flowers and buds, so that the plant continues to expand, topdressing once every 15-20 days. more buds will be formed after September to make them bloom on National Day.

Pest control

Sometimes brown spot and powdery mildew occur, which can be controlled by spraying more than 50% carbendazim.

1. African impatiens powdery mildew

Symptoms the disease mainly occurs on leaves and shoots. It usually begins in June, and the leaves are covered with white powder layer after July. Subsequently, small yellow dots were formed in the powder layer, and the color gradually darkened, and finally showed dark brown. The pathogens overwintered in the remnants of diseased plants and seeds. The following year, when the environment is suitable, the germs spread by wind and rain. The peak period of disease is from August to September.

[control methods] planting is not too dense, proper ventilation, strengthen fertilizer and water management, enhance plant disease resistance. Remove diseased leaves and diseased plants and destroy them centrally so as to reduce the source of infection. During the onset of the disease, 15,000,1200 times solution of the wettable powder or 1000 times solution of the 70% methyl topiramate wettable powder were used for prevention and treatment. Avoid spraying at a high temperature above 32 ℃ to avoid drug damage.

2. Brown spot of African impatiens

African impatiens brown spot, also known as impatiens leaf spot. Symptomatic diseases mainly occur in leaves. The foliar spot is a light yellowish brown spot at first, then expands into a circle or oval, and then the center becomes light brown, the edge is brown, with inconspicuous rims. On the seriously diseased leaves, there are a series of disease spots, which causes the leaves to become withered and yellow until the plant dies. The pathogen overwintered on the remains of the disease and the fragments of soil and plants. The following year, when the environmental conditions were suitable, the germs spread by means of wind and rain. It is easy to get sick in the high temperature and rainy season.

[control methods] African impatiens prefers fertile sandy loam and is not resistant to waterlogging. Therefore, it is appropriate to plant sandy loam to facilitate drainage; potted African impatiens should be poured out in time after rain. Diseased leaves and plants should be destroyed at the end of autumn to reduce the source of infection in the coming year. The initial stage of the disease with 25% carbendazim wettable powder 300 times 600 times liquid, or 50% methyl topiramate 100 times solution, or 75% chlorothalonil 1000 times solution for prevention and treatment.

3. African impatiens blight

The symptomatic pathogen mainly infected the rhizome, the pathogenic part blackened or constricted, and white mildew appeared on it when it was moist. After the plant was infected, the leaves wilted and withered within a few days, resulting in the death of the whole plant. It overwinters mainly in the form of mycelium or sclerotia in the soil or in the sick and disabled body, and the mycelium camp in the soil is saprophytic and does not dormant. In the field, it is mainly transmitted by contact, that is, when the roots, stems and leaves of the plant come into contact with the diseased soil, it will be infected by the hyphae in the soil. Under the condition of water film, the healthy leaves in contact with the diseased part will be infected. In addition, seeds, farm tools and bacteria-carrying compost can spread the disease.

[prevention and control methods] after the diseased plants were removed at the initial stage of the disease, 75% chlorothalonil wettable powder was sprayed with 600x liquid, or 60% Fufu wettable powder 500x liquid, 20% methyl rifampicin EC 1200 times.

Sowing and Cuttage Propagation of African Impatiens

African impatiens commonly used reproduction methods, there are two propagation methods of sowing and cutting, the two propagation methods can be carried out throughout the year, generally better reproduction in spring and autumn, flower friends can combine their own conditions, choose appropriate breeding methods, the following respectively sort out African impatiens seed sowing and cutting propagation methods, hoping to help flower friends better breed African impatiens.

Propagation methods of African impatiens 1. Sowing and propagation methods

African impatiens can be sown all year round to prepare the seeds of African impatiens, which are small, 1700 to 1800 seeds per gram, and are sown with a mixture of sterilized culture soil, rotten leaf soil and fine sand. The optimum temperature for germination was 22 ℃ and germinated 15-20 days after sowing. The optimum temperature for germination of New Guinea Fengxian was 24: 26 ℃, and germinated 7-14 days after sowing.

1. The method of cutting propagation

The cuttage propagation of African impatiens can generally be carried out throughout the year, but it is the best in spring and autumn. First, the sturdy top branches with a length of 10 cm to 12 cm are selected, and the branches are inserted into the sand bed at 20 to 25 degrees. Generally, it takes about three weeks after cutting to take root and survive.