Growth period Management of Gladiolus cut Flower production Technology in Open Field (part I)

1. Moisture

Gladiolus should keep the soil moist before emergence so that the bulbs can take root quickly. In general, the soil water holding capacity should be about 25%, while the aeration condition of the soil should keep the porosity between 5% and 10%. 3The 7-leaf stage is not only the period of flower bud differentiation and inflorescence elongation, but also the period of traction root formation and rapid growth. Once the water supply is insufficient, it will obviously affect the quality of cut flowers. If the seed is harvested after flowering, stop watering 1-2 weeks before pilling. Sprinkler irrigation and drip irrigation are better for gladiolus field irrigation, which can not only maintain better soil structure, improve ambient air humidity, prevent leaf tip withering, but also save water. Irrigation can be carried out in the morning, which is beneficial to reduce the temperature near the leaves during the day and increase the air relative humidity, while the dry plants at night are beneficial to reduce the invasion of diseases. When planting in the open air, Rain Water should pay special attention to drainage and waterlogging prevention in more areas and seasons to avoid root rot. Especially when it is flooded at the stage of 3-4 leaves, the flower branches cannot be extracted. Long-term flooding will make the flower branches fragile and easy to break, the flowers are small, the scorched leaf tips will be aggravated, making the cut flowers lose their commercial value.

II. Fertilization

Gladiolus likes fertile soil, but it should not be fertilized too much. Correct fertilization should be carried out according to soil type, soil fertility, salt content and other specific conditions. The application of organic fertilizer is beneficial to the improvement of soil structure, and at the same time, it can avoid using a large amount of chemical fertilizer and make the soil salt content too high. Gladiolus is very sensitive to soil salinity. Too high salinity will inhibit the growth of roots and absorb water, which will affect the growth of the whole plant and reduce the quality of cut flowers. Special attention should be paid to the side effects of fluoride and chlorine on Gladiolus. When using phosphate fertilizer, it must not contain fluoride. For this reason, triphosphate (which is easy to contain high concentration of fluoride) should be used as little as possible, and other phosphate fertilizers should be used instead to prevent the leaf tip from scorching.

1. Application time

Gladiolus can be fertilized many times in the whole growth cycle, including base fertilizer before planting and three times of topdressing in the growing period.

The base fertilizer is mainly organic fertilizer, and the mature organic fertilizer can improve the physical structure and chemical properties of the soil, make the soil loose, have good ventilation, conserve water and fertilizer, and promote root growth, and the organic fertilizer has slow release and long-term effectiveness. it can ensure sufficient nutrient supply in the whole cycle of plant growth. The amount of organic fertilizer applied depends on the original fertility of the soil. Generally speaking, the content of soil organic matter should be kept at about 2% to 3%. Chemical fertilizer is mainly used as topdressing. Chemical fertilizer has the characteristics of quick effect and strong wastage, so it is not suitable to apply more in base fertilizer. Because after planting, the root system of the plant has not been fully developed, and a large amount of chemical fertilizer is applied, which results in the increase of soil salinity and affects the normal growth of the plant. Phosphate fertilizer is not easy to lose in the soil, so it can be applied together with base fertilizer under the premise of considering salt concentration. In short, it is necessary to analyze and evaluate the soil before fertilization in order to achieve reasonable fertilization.

Topdressing should be applied three times during the growth period of Gladiolus: the first time when the plant of Gladiolus grows to 2-3 leaf stage. At this time, it is the stage of flower bud differentiation, and the stored nutrients in the bulb have been consumed massively. If there is a lack of water and fertilizer, the number of florets in the inflorescence will decrease and the quality of cut flowers will decline. Nitrogen and potassium fertilizer is the main fertilizer this time. The second time is in the 5-leaf stage. At this time, the flower stem elongates rapidly, the development of a single floret is accelerated, and the fertilizer is mainly phosphorus and potassium fertilizer, which can promote the sturdy flower branches, large and bright flowers and long vase life after harvest. The third time after cut flowers were harvested. At this time, it is the period of growth and development of new balls and bulbs, and fertilizer is needed to support the growth of corms. The plumpness of the bulb and the amount of stored nutrients directly affect the growth potential of the next year, while the number of bulbs affects the reproduction rate. Therefore, topdressing after anthesis is very important and can not be ignored. Topdressing can be supplemented by root fertilization and foliar fertilization, and combined with irrigation to give full play to the effect of fertilizer. The chemical fertilizers used for topdressing Gladiolus include ammonium nitrate, potassium nitrate, calcium superphosphate, potassium dihydrogen phosphate, ammonium sulfate, potassium sulfate, urea and so on. Use less potassium chloride and fluorine-containing phosphate fertilizer.