Key Fertilization Techniques for Open-Field Bell Pepper Cultivation
Bell pepper belongs to the plant kingdom, class Dicotyledoneae, subclass Asteridae, family Solanaceae. Together with red chili peppers, it is collectively called pepper. The fruit is a berry. It has many aliases - big pepper, lantern pepper and persimmon pepper are all names for it; because it can produce sweet berries, it is also called sweet pepper or vegetable pepper. It is an annual or perennial herbaceous plant, characterized by relatively large fruit with a mild pungency or no pungency at all, eaten as a vegetable rather than used as a seasoning. Because it is bright green and vivid, and newly bred varieties also come in red, yellow, purple and other colors, it can not only stand alone as a dish but is also widely used as a side ingredient. Bell pepper evolved in North America from chili peppers native to the tropical regions of Central and South America. Through long-term cultivation, domestication and artificial selection, the fruit underwent trait changes such as increased volume, thicker flesh, loss of pungency, and an increased number of carpels and ovary chambers. It was introduced to China more than 100 years ago and is now widely cultivated throughout the country. Bell pepper is rich in vitamin C and is suitable for people with high blood pressure and high blood lipids.
Morphological characteristics of bell pepper
Bell pepper evolved in North America from chili peppers native to the tropical regions of Central and South America. Bell pepper is nutritious, with mild pungency or hardly any pungency at all, and is eaten as a vegetable rather than used as a seasoning. Because it is green and graceful, it has various variant cultivars, including yellow, green, red and others.
How should fertilization be carried out for open-field bell pepper cultivation?
Bell pepper is rich in protein, sugars, organic acids, vitamins and various inorganic salts, and its vitamin C content is among the highest of all vegetables, at 73-342 mg per 100 grams of fresh fruit. The growth cycle of bell pepper includes three stages: the germination stage, the seedling stage and the flowering and fruiting stage. The germination stage runs from seed sprouting to the appearance of true leaves; the seedling stage runs from the appearance of true leaves to the emergence of the first flower bud, during which basic vegetative growth and flower bud differentiation must be completed; the flowering and fruiting stage runs from the emergence of the first flower bud to uprooting. In the early part of this period (from the emergence of the first flower bud to the setting of the first fruit), water should be appropriately controlled to prevent flower drop. After that, the plant enters the fruiting stage, when fertilizer and water management should be strengthened, the leaves protected, plant growth maintained, the relationship between vegetative growth and reproductive growth coordinated, and both vines and fruits promoted to thrive, so as to extend the harvest period and achieve a high yield.
Bell pepper is not strict about soil requirements; generally sandy soil and clay soil are both suitable for cultivation, but loam that is fertile, deep and well drained is best. Bell pepper has relatively high soil nutrient requirements. If nutrition is inadequate, especially if nitrogen is insufficient or excessive, or if phosphorus fertilizer is insufficient, this often leads to heavy dropping of flowers, buds and young fruits; potassium should be somewhat less than nitrogen, otherwise stem and leaf development will be poor. Because the root system of bell pepper is not well developed, it has strict water requirements. Based on the growth characteristics and nutrient requirements of bell pepper, the fertilization principles are:
1) Apply heavy base fertilizer. Bell pepper has a long growth period, so applying sufficient base fertilizer is very important. That is, on the basis of applying sufficient farmyard manure, apply 45-50 kg per mu of “Tianji” brand nitric phosphate potassium fertilizer.
2) Apply frequent topdressing. When the first fruit reaches 2-3 cm in diameter, apply 10 kg per mu of “Tianji” brand nitric phosphate fertilizer together with the fruit-promoting watering; when entering the peak fruiting period, apply 15 kg per mu of “Tianji” brand nitric phosphate fertilizer together with hilling; after entering the rainy season, to prevent plants from losing nutrients after rain, apply 15 kg per mu of “Tianji” brand nitric phosphate fertilizer; when entering the second flowering and fruiting period, to ensure rapid fruit enlargement, apply 20 kg per mu of “Tianji” brand nitric phosphate fertilizer together with watering.
3) Storage season: choose late-autumn fruits for harvest, and be sure to harvest before frost to avoid frost damage or chilling injury; peppers that have suffered frost damage or chilling injury cannot be used for storage or long-distance transport. Fruits from uprooted plants after autumn are not suitable for storage. The storage entry time should be determined according to the local frost arrival time, and storage should begin half a month before frost (when the nighttime temperature falls below 10°C). The general principle is to store as late as possible according to weather changes, provided there is no frost damage or chilling injury.
4) Field management: be sure to choose plots with good field cultivation management and reasonable agricultural technical measures, and pay special attention to pest and disease control before harvest, so as to produce robust fruits and provide high-quality bell peppers for storage. Fruits produced in plots with poor field management and many pests and diseases are not suitable for long-term storage and transport.
5) Irrigation and rain: it is emphasized that irrigation should stop 5-7 days before harvest; irrigation before harvest will greatly increase rot in stored bell peppers. Peppers exposed to rain cannot be stored.
6) Harvest time: picking should generally be carried out on clear mornings or evenings when the air temperature and vegetable temperature are relatively low. Fruits should not be picked on rainy days, foggy days or days with scorching sun exposure, otherwise the fruits are prone to increased rot and accelerated aging.