When do potted oranges bloom? The flowering period is from April to May, and the fruiting period is10-65438+February.
Flowers are solitary or 2-3 in clusters, with irregular 5-3 split flowers. Petals are usually less than 65438 0.5 cm long, stamens are 20-25, and the style is slender and the stigma is head-shaped. The flowers of citrus are mixed flowers, which have branches, leaves and flowers after germination. Flowers are divided into single flowers and inflorescences: red orange and satsuma mandarin, sweet orange, lemon and grapefruit have inflorescences besides single flowers, and pomelo is mainly inflorescence. Citrus usually needs pollination and fertilization to bear fruit, but mandarin oranges and navel oranges can bear fruit without fertilization. This is parthenocarpy, also called parthenocarpy.
Citrus growing environment
temperature
The growth, flowering and fruiting of citrus trees are closely related to temperature, sunshine, moisture (humidity), soil, wind, altitude, topography, slope direction and other environmental conditions, among which the temperature has the greatest influence. Even if the temperature difference is 0.5℃, sometimes there will be completely different results. The growth and development of citrus fruits need a temperature of 65438 02.5 ~ 37℃. The day and night temperatures of flower bud differentiation in autumn are about 20℃ and 65438 00℃, respectively, and the soil temperature of root growth is roughly the same as the ground temperature. If the temperature is too low, oranges will freeze. When the sweet orange is at -4℃ and the satsuma orange is at -5℃, the branches and leaves will be frozen. When the sweet orange is below -5℃ and the satsuma orange is below -6℃, the branches will be frostbitten. When the sweet orange is below -6.5℃, the satsuma mandarin will freeze to death.
Slightly resistant to shade, like warm and humid climate, not cold-resistant, freezing injury occurs when the temperature is lower than -8℃, and it is suitable for growing in deep and fertile neutral to slightly acidic sandy loam.
High temperature is also not conducive to the growth and development of citrus. When the air temperature and soil temperature are higher than 37℃, fruits and roots stop growing. Temperature also has obvious influence on fruit quality: in a certain temperature range, with the increase of temperature, the sugar content and soluble solids increase, the acid content decreases and the quality becomes better.
illuminate
Citrus is a tree species with strong shade tolerance, but good sunshine is needed for high quality and high yield. Generally, areas with annual sunshine hours 1200 ~ 2200 hours can grow normally. For example, compared with Chongqing citrus producing areas with less sunshine, South China with good sunshine and abundant calories has higher sugar content, lower acid content and higher sugar and acid content.
humidity
Generally, tropical and subtropical regions with annual rainfall of about 1000mm are suitable for citrus planting, but irrigation is often needed because of uneven distribution of annual rainfall. The suitable relative water content of soil is 60% ~ 80%, and irrigation is needed when it is lower than 60%. Too much rain will cause soil water accumulation or high groundwater level and poor drainage in citrus orchards, resulting in root death. Citrus fruit trees require that the air relative humidity should be around 75%.
land
Citrus can adapt to a wide range of soils. Purple soil, red and yellow soil, beaches and beaches can all grow at ph 4.5 ~ 8, and ph 5.5 ~ 6.5 is the most suitable. The growth of citrus roots needs high oxygen content, and the soil with loose texture, good structure, organic matter content of 2% ~ 3% and good drainage is the most suitable.
Citrus cultivation techniques
It is required that the soil layer is deep (60㎝) and fertile; The slope of the orchard is less than 25 degrees. When planning a garden, there should be necessary roads, irrigation and drainage, water storage and ancillary building facilities. In terms of specific planning, we should concentrate on one place as much as possible and build gardens in places with good traffic and water conditions.
time
It is usually planted from February to March when spring buds sprout.
soil management
It is necessary to dig holes and solidify soil, prohibit planting tall plants such as corn and wheat in the garden, and do a good job in rational intercropping and intertillage weeding in the orchard.
Fertilizer and water management
(1) Fertilization principle: It is necessary to fully meet the demand of blood oranges for various nutrient elements, advocate more application of organic fertilizers, and rationally apply inorganic fertilizers and formula fertilizers. According to the results of leaf analysis, orchard soil analysis and blood orange phenology, fertilization is guided.
(2) Fertilization methods: mainly soil fertilization and foliar fertilization. The methods of annular furrow application, strip furrow application, hole application and soil surface fertilization were adopted.
(3) Fertilization of young trees: apply less fertilizer, mainly nitrogen fertilizer, with phosphorus and potassium fertilizer, and apply fertilizer 5-6 times in spring, summer and autumn when bamboo shoots emerge, (March, May, June, July, September, 65438+February, and apply 0.4 kg ammonium bicarbonate or 0.2 kg urea to each plant each time. 1-3 young trees should be applied with pure nitrogen 100-400g every year, and the ratio of nitrogen, phosphorus and potassium is1.0: (0.4-0.5):1.0. Adult trees should be fertilized four times, that is, germination accelerating fertilizer, fruit protection fertilizer, fruit strengthening fertilizer and fruit picking fertilizer. Generally, the amount of fertilizer applied is 2-3 kg of chemical fertilizer and one load of manure. Fruit-keeping fertilizer 1-2 kg phosphorus and potassium fertilizer+1 kg chemical fertilizer; Strong fruit fertilizer 1-2 kg chemical fertilizer+1-2 kg phosphorus and potassium fertilizer; The fruit picking fertilizer (base fertilizer) is mainly organic fertilizer, and each plant is applied with 50- 100 kg organic fertilizer+1-2 kg chemical fertilizer.
(4) Moisture: Irrigation when soil is dry, and drainage when water accumulates.
Plastic trimming
principle
Adjust measures to local conditions, prune trees, properly raise and lower them, and ventilate and transmit light to achieve three-dimensional effect.
Do plastic surgery
(naturally happy). The trunk is 20-40cm high, and the trunk branches (3-4 branches) are scattered on the trunk. The branching angle of the main branch is 30-50 degrees, and 2-3 auxiliary main branches are left on each main branch. Generally, after the third main branch is formed, the central trunk of this kind is cut off and twisted to one side to form a fruiting branch group.
decrease
(1) Young trees: mainly light pruning. After selecting the extension branches of the class center and the main branches and the extension branches of the auxiliary main branches, moderate or even severe pruning is carried out, and the growth balance among the main branches is adjusted according to the pruning degree and the direction of cutting buds. In addition to properly thinning the over-dense branches, the inner branches and weaker branches in the middle and lower part of the crown should generally be retained.
(2) Initial fruiting stage: continue to select short cutting to treat the trunk extension branches at all levels, erase the summer shoots, and promote the autumn shoots to be robust. In autumn, measures such as ring cutting, root cutting and water control are taken to promote the flowering of Wangshu.
(3) Full-fruiting period: the fruiting branches, falling branches and declining branches are retracted in time, and the light-blocking branches, dead branches and insect branches are cut off.
Eliminate pests and diseases
root rot
Timely drainage, improve the lighting and ventilation conditions in the park, and strengthen the prevention and control of trunk pests such as longicorn beetles; Selecting disease-resistant rootstocks such as Fructus Aurantii, Fructus Aurantii Orange and tangerine, and replacing infected plants with disease-resistant rootstocks.
mite
Before and after flowering (March-May) and autumn (9-165438+1October) are the key periods for controlling red spider: the population density reaches 1-2 heads/leaf before flowering, and it needs to be controlled after flowering and when it reaches 5-6 heads/leaf in autumn. The main periods of controlling rust lice are spring shoot sprouting, young fruit and fruit expansion: rust color appeared on the back of spring shoot leaves in that year; When the insect population density on leaves or fruits reaches 2-3 heads per leaf, control it immediately. Commonly used pesticides include hexythiazox, fenpropathrin, propargite, bromopropyl ester, chlorfenuron and so on. Pay attention to protect natural enemies, such as bearded mites, blunt mites, lacewings, etc.
balance
The key period of drug control: the first generation nymph stage of scale insects, the damage stage of a large number of terminal branches in the larval stage of scale insects (usually from early May to mid-June), and the peak period of scale insects. Commonly used drugs include buprofezin, methidathion, matrine+nicotine, levobuprofezin, oil emulsion and so on. Pay attention to improving the ventilation and light transmission conditions in the park; Protect and utilize natural enemies such as Japanese square beetles, red-lipped ladybugs, lacewings, golden aphids, Australian ladybugs and red ladybugs.
aphid
The killing rate of new shoots is 25%, and it should be sprayed immediately. Commonly used pesticides include chlordimeform, dimethoate and butachlor. Attention should be paid to the protection of ladybugs, Chrysopa grandis, aphid bees, etc. Cut off the overwintering eggs and reduce the pest base.
Leaf miner
The key period of control is the emergence of bamboo shoots in summer and autumn (mid-July). Wipe off the scattered new shoots in summer and autumn in time, and combine fertilizer and water management to promote the healthy and tidy new shoots of plants. Chemical control: spray new shoots every 7- 1-2cm for 2-3 times continuously. Commonly used pesticides are avermectin, cartap and cypermethrin.
Cerambycidae
From May to August, the adults of Anoplophora glabripennis and Anoplophora glabripennis were killed artificially at noon on sunny days, and the adults of Anoplophora glabripennis were killed in the evening; Remove eggs and newly hatched larvae in time and cut off damaged branches; Soak pesticides such as dimethoate in cotton or cotton yarn, then block the wormhole, and then seal the wormhole with soil to poison the larvae.
Bud maggot
When budding, methyl chloride powder, diazinon granules, etc. After selection, it is mixed with fine soil and sprinkled on the soil surface of the tree tray once every 7 days for 2-3 consecutive times; When the diameter of the bud is 2-3mm (white), spraying phosphorus and trichlorfon on the crown; Remove the damaged flower buds as soon as possible, and concentrate or boil them deeply; Deep digging in the garden soil in winter can kill some overwintering pests pupae.
Fruit harvesting
According to the maturity, use and market demand of citrus fruits, the harvesting time is determined. It is not suitable to pick fruits in rainy days and when the dew on the fruit surface is not dry. People who pick fruit should wear gloves, cut the fruit together with the fruit handle with a round-headed fruit scissors, then cut the fruit pedicle flat and handle it gently. Pick fruits from outside to inside and from top to bottom. The inner wall of all fruit containers should be smooth, and the harvested fruits should be transported to the packaging yard or storage warehouse in time. Avoid sun and rain.
The main value of oranges
Oranges are bright in color, sweet and sour, usually orange. They are one of the most common fruits in people's lives, and their peels can be used as medicine.
Oranges are sweet and sour, warm in nature and enter the lungs. It is mainly used to treat chest and diaphragm qi stagnation, vomiting, loss of appetite, deficiency of stomach yin, dry mouth, cough due to lung heat, and excessive drinking. Has effects in stimulating appetite, quenching thirst, and moistening lung. Oranges are also very nutritious, and an orange can almost meet the vitamin C content needed by the human body in one day. Oranges contain 170 kinds of plant compounds and more than 60 kinds of flavonoids, most of which are natural antioxidants.
The rich nutrients in oranges have the functions of reducing blood fat and anti-atherosclerosis, which is of great benefit to the prevention of cardiovascular diseases. Orange juice contains a substance called "nomilin", which has the ability to inhibit and kill cancer cells and has a preventive effect on gastric cancer. The orange peel is orange-red, and the pulp is granular, much like grapefruit. Orange peel is thin and fleshy, and the juice is sweet and sour. Peel off the orange peel and the orange juice will overflow.
Citrus fruits are rich in nutrition and good in color, smell and taste. It can be eaten fresh or processed into various processed products, mainly fruit juice. Citrus production ranks first among 100 fruits, and citrus juice accounts for 3/4 of juice, which is widely favored by consumers. According to the analysis of the Central Institute of Health, the edible part of citrus contains 0.05mg of riboflavin, 0.3mg of nicotinic acid, 0.6 mg of ascorbic acid (vitamin C), 0.9g of protein, 0. 1g of fat, 0/2g of sugar 12g of crude fiber and 0.2g of inorganic salt. The content of carotene (provitamin A) in citrus is second only to apricot and higher than other fruits.