How to grow petunia?

Petunia is actually not morning glory, the scientific name is Bidong eggplant, it is a perennial herb of the genus Solanaceae, also known as shuttlecock flower, short trumpet, sweet potato flower, etc., native to Argentina in South America and widely cultivated all over the world. China's north and south city parks are widely cultivated and ornamental, and the climate is suitable or greenhouse cultivation can blossom all the year round. Let's take a look at the planting method of petunia.

Growth habits of Petunia

Petunia prefers warm and sunny environment, can not tolerate frost, fear rain and waterlogging, the suitable temperature for growth is 13: 18 ℃, winter temperature is 4: 10 ℃, if the plant growth stops below 4 ℃, it can withstand high temperature above 35 ℃ in summer. The summer high temperature season should be watered in the morning and evening to keep the basin soil moist. There are more Rain Water in the rainy season, which is very disadvantageous to the growth of Petunia. If the pot soil is too wet, the stems and leaves are easy to grow, the flowering period is Rain Water, the flowers are easy to fade or rot, and if the basin soil is stagnant for a long time, the rotten roots die. Therefore, potted petunia should use loose, fertile and well-drained sandy loam. Petunia is a long sunshine plant, which requires sufficient sunshine during the growing period. under normal light conditions, it takes about 100 days from sowing to flowering.

Sowing and reproduction of petunia

Petunia can sow and raise seedlings all the year round in the protected areas of the middle and lower reaches of the Yangtze River. because the florescence is generally controlled on May Day and National Day, the sowing time is from October to November and from June to July. Install the medium before sowing, pour water thoroughly, and wet the seeds with fine spray after sowing. The seeds can not be covered with any medium, otherwise it will affect germination. After sowing, the medium temperature was kept at 22: 24 ℃, and seedlings emerged at 4: 7 days. After the appearance of the first pair of true leaves, 50 × 10 ~ 6 concentration of nitrogen fertilizer solution was applied and ventilation was paid attention to, so that the seedlings could gradually see light. When 2-3 pairs of true leaves appeared in the seedlings, the medium temperature could be reduced to 18-20 ℃, and 0.1% urea solution or 0.1% compound fertilizer solution of 15-15-15 nitrogen, phosphorus and potassium was applied every 7-10 days. At this stage, attention should still be paid to ventilation to prevent diseases, and chlorothalonil or methyl topiramate 800 / 1000 times should be sprayed every week or so. When there are three pairs of true leaves in the plant, the root system has been formed intact, and the requirements of temperature, humidity and fertilization are the same as before, so we should still pay attention to ventilation and disease prevention.

How to grow petunia?

1. Fertilization: petunia like fertilizer, and there is a great difference between using fertilizer or not. After 4 true leaves, 2000 times of Biwang is fertilized once a week, 1500 times of Biwang is fertilized once a week, and a little slow-release fertilizer can be added during pseudo-planting. 1000 to 1500 times of Biwang is fertilized twice a week when it is planted to the full stage of the plant, and 1000 times as much as 1000 times from the bud to the blooming stage mixed with twice a week, sometimes the dwarf will be iron deficient. You can add some ferrous sulfate.

2. Watering: Petunia likes to be dry and afraid of dampness. In the process of growth, it needs plenty of water, especially in the hot summer season. It can be watered in the morning, noon and evening in order to keep the basin soil moist, but do not cause stagnant water in the basin. Otherwise, long-term stagnant water in the basin will cause rotten roots, cause plant death, and do not be too wet, otherwise it is easy to cause stems and leaves to grow too long.

3. Illumination: Petunia is a long-sunshine plant, which requires plenty of sunshine during the growing period. under normal light, it takes about 70-90 days from sowing to flowering in most petunia breeds. If the light is insufficient or there are too many cloudy and rainy days, the flowering of the plant is often delayed by 10-15 days, and the flowering is less. If the plant grows in long sunshine in spring and summer, the plant will bud quickly, and the time from sowing to flowering is only about 60-70 days.

4. Temperature: Petunia prefers a warm environment, and the most suitable temperature for its growth is that some varieties can withstand a high temperature of more than 35 ℃ in summer, but the plant grows slowly and most varieties will stop growing. The winter temperature is 4-10 ℃. If the temperature is below 4 ℃, the growth of the plant will stop and it will not be frozen in the low temperature of-2 ℃.

5. Pruning: generally, petunia do not need to pick the heart, but some varieties need to pick the heart, which can be carried out when the seedling stage is 5 to 6 centimeters high. Generally speaking, bud thinning is not needed throughout the growth period, but sometimes bud thinning is used to control florescence. Under the condition of high temperature and humidity in summer, the plant is easy to lodge, pay attention to pruning, remove the residual flowers, to achieve luxuriant flowers and leaves. If old, diseased or withered leaves are found in the course of its growth, they should be removed at any time. After overwintering, the old plant can be re-cut in early spring when it changes pots, and nitrogen fertilizer should be applied once or twice after cutting to make it recover, grow and bloom again.

6. Diseases and pests: the common diseases of petunia are mildew, leaf spot, virus, aphids and so on.

① white mildew: remove the diseased leaves in time after the onset of the disease, and spray 75% chlorothalonil 600 times 800 times at the initial stage of the disease.

② leaf spot disease: try to avoid bruising leaves and pay attention to prevent wind damage, sunburn and freezing injury, timely removal of diseased leaves and burn, pay attention to remove fallen leaves, spray 1000 times of Dysenamine solution.

③ virus disease: the indirect control method is to spray insecticides to control aphids, spray 40% omethoate 1000 times solution, and disinfect tools and hands that have come into contact with diseased plants in cultivation operations.

④ aphids: when a large number of aphids are found, they should be isolated in time and sprayed with 1000 times of omethoate emulsion or 1000 times of Mala sulfur emulsion or 1000 times of dichlorvos EC or 15000 times of imidacloprid water dispersible granules.