How to Fertilize Gladiolus? Detailed Guide to the Latest Methods
Known as the king of cut flowers, gladiolus, also called sword lily, can be used not only as a cut flower but also for potted plants and flower bed arrangements. Recently, many readers have asked us about gladiolus fertilization methods, so how do you fertilize gladiolus? Simply put, before planting gladiolus, the soil should be given sufficient base fertilizer, and the best type of base fertilizer is one rich in phosphorus and potassium. Before and after flowering, apply 1 to 2 times of well-rotted dilute organic fertilizer; after flowering, apply more potassium fertilizer to promote the growth of cormels. The specific fertilization methods for gladiolus are described below:
Gladiolus likes fertile soil, but fertilizer should not be applied excessively. During the growth process of gladiolus, fertilizer can be applied multiple times, generally divided into base fertilizer before planting and 3 topdressings at key growth stages. The base fertilizer is mainly organic fertilizer. Fully rotted organic fertilizer can improve the physical and chemical properties of the soil, adjust soil structure, make the soil loose, improve water permeability and water retention, and promote good root growth. Even more beneficial is the slow-release and long-lasting nature of organic fertilizer, which can provide nutrient supply for the entire growth cycle of the plant. When applying base fertilizer, some quick-acting chemical fertilizer can be used together, but it should not be applied in large amounts.
Fertilization should be carried out according to the specific conditions of cultivation type and purpose, soil type and fertility, total soil salt content, and the plant's growth stage. Because gladiolus is sensitive to soil salinity, fluorine, and chlorine, care should be taken in choosing fertilizer types. Use as little triple superphosphate as possible (it easily contains high concentrations of fluorine), and replace it with other phosphorus fertilizers, which can effectively avoid leaf tip scorch. Topdressing can be carried out by combining root fertilization and foliar fertilization, and combined with irrigation, to give full play to fertilizer efficiency. Chemical fertilizers that can be used for topdressing include: ammonium nitrate, potassium nitrate, superphosphate, monopotassium phosphate, ammonium sulfate, potassium sulfate, urea, etc. Use as little potassium chloride and fluorine-containing phosphorus fertilizer as possible.
The suitable time and type of fertilization are determined according to its growth and development characteristics. The first time is after the plant has unfolded 2 leaves, and the fertilizer is mainly nitrogen and potassium fertilizer. At this time, it is the floret differentiation stage, and the nutrients in the originally planted corm have been largely consumed. If fertilizer and water are insufficient at this time, the number of florets in the inflorescence will decrease, affecting the commercial value of the fresh cut flowers. The second time is after the 4-leaf stage, when the flower stem begins to gradually elongate and the development of individual florets accelerates. The fertilizer is mainly phosphorus and potassium fertilizer, to promote thick and strong flower stems, make the flowers large and brightly colored, and give a long vase life after cutting. The third time is after flowering, which is the period of growth and development of new corms and cormels, requiring large amounts of nutrients to promote the full development of new corms. The degree of plumpness of the planting corms and the number of cormels will have a relatively large impact on the cut flower production and expansion of propagation in the next year, and the fertilizer is still mainly phosphorus and potassium fertilizer.
Throughout the entire growth period of gladiolus, topdressing should be applied 2 times. The fertilizer should be mainly phosphorus fertilizer, supplemented by nitrogen fertilizer. The first time is after 2 leaves have unfolded, apply 40 kg per mu of compound fertilizer with 15% each of nitrogen, phosphorus, and potassium to promote vegetative growth; the second time is at the 4-leaf stage (flower bud differentiation stage), apply 25 kg per mu of compound fertilizer and 5 kg of potassium fertilizer to promote thick and strong flower stem growth. Note that when fertilizing, the compound fertilizer must be dissolved in water and then diluted into liquid fertilizer for application. After growing to 5 leaves, a 1% concentration solution of monopotassium phosphate or Xinzhisu can be sprayed as a foliar topdressing every 5 to 7 days. In addition, at the 4-leaf stage, 25 kg per mu of lime powder can be broadcast to neutralize soil acidity and reduce the occurrence of diseases later.
Precautions:
Organic fertilizer is commonly known as farmyard manure. It mainly uses the supply of organic matter as a means to improve the physical and chemical properties of the soil, promote plant growth, and promote the cycling of the soil ecosystem. Some broad categories of organic fertilizer include:
Compost: a fertilizer made from various crop stalks, fallen leaves, green grass, animal and plant residues, and human and livestock manure as raw materials, mixed together in proportions or mixed with a small amount of soil and subjected to aerobic fermentation and decomposition.
Waterlogged compost: the raw materials used are basically the same as those for compost, but it is fermented under submerged conditions.
Biogas fertilizer: a byproduct after organic matter decomposes and produces biogas in a sealed biogas digester, including biogas slurry and residue.
Green manure: the use of cultivated or wild green plant bodies as fertilizer. Examples include leguminous mung bean, broad bean, sweet clover, sesbania, alfalfa, hairy vetch, etc. Non-leguminous green manures include ryegrass, fodder radish, niger seed, Azolla, water hyacinth, alligator weed, etc.
Crop straw: crop straw is one of the important fertilizer types. Crop straw contains nutrient elements essential to crops such as n, p, k, ca, s, etc.
Under suitable conditions, through the action of soil microorganisms, these elements return to the soil after mineralization and are absorbed and utilized by crops.
Pure natural mineral fertilizers include potassium mineral powder, phosphorus mineral powder, calcium chloride, natural potassium-magnesium sulfate fertilizer, and other natural substances that have not undergone chemical processing. Such products must pass organic certification and be produced strictly according to organic standards before they can be used in organic agriculture.
Cake fertilizer: rapeseed cake, cottonseed cake, soybean cake, sesame cake, castor cake, tea seed cake, etc.
Mud fertilizer: unpolluted river mud, pond mud, ditch mud, harbor mud, lake mud, etc.