Detailed Explanation of Flower Promotion Measures and Methods for Mandarin Oranges
In our country, mandarin oranges are a very common and highly popular fruit. According to what the editor has learned, mandarin oranges from Guangxi are quite famous, which shows that mandarin oranges are suited to living in places with relatively hot weather, and in the north it is impossible to grow delicious mandarin oranges.
Flower Promotion Measures and Methods for Planting Mandarin Oranges
The factors that affect mandarin orange flowering include: variety, rootstock, tree age, moisture, climate and soil conditions, cultivation techniques, etc. The commonly used agricultural flower promotion measures include 4 points:
1. Chemical flower promotion:
Paclobutrazol: after the autumn shoots mature, spray 500 ppm paclobutrazol (that is, 15% paclobutrazol diluted with water at 300 times), and spray a second time after 20-30 days; this is a safe and effective method.
2. Root cutting for flower promotion:
For paddy fields and orchards with relatively shallow root systems, carry out root cutting after harvest or in December. Hoe the soil around the canopy to cut roots; for young trees and vigorous trees, hoe 4-5 cun deep, while middle-aged fruiting trees should be hoed shallowly; part of the surface roots must be cut and exposed to the sun until the leaf color slightly fades to green for it to be effective. Root cutting is also a relatively safe flower promotion method, and the effect is even better if combined with water control.
3. Girdling or tying iron wire for flower promotion:
For strong and vigorous trees with deep main roots, girdling is suitable for flower promotion. Girdling is carried out in mid-to-late December; young trees can be girdled on the main trunk, while for large trees it is better to girdle the main branches, with the degree being to cut through the phloem without injuring the xylem. About 1 week after girdling, the canopy can be seen fading green. For young and vigorous trees entering production that use deep-rooted rootstocks (such as sour orange), if the leaf color is still deep green and has not faded by mid-to-late January, girdling can be done once more. Girdling is a strong flower promotion method; if leaf drop occurs after girdling, water promptly, and irrigate and fertilize early in spring to strengthen shoots and flowers. After girdling, pesticides with strong irritants such as lime sulfur mixture and rosin mixture must not be sprayed. Spraying 10-20 ppm 2,4-D mixed with 0.3 monopotassium phosphate or nucleotides, etc. can greatly reduce abnormal leaf drop.
Tying iron wire means using No. 14-16 iron wire to bind the trunk and branches so that 2/3 of the iron wire sinks into the bark without injuring the xylem. Trees 2-5 years old can have the main trunk tied, and for those with thick trunks, branches with a diameter of 3-4 cm can be tied; after 1 month, remove the iron wire depending on the change in leaf color.
4. Branch bending and twisting: Young fruiting trees, especially strong and vigorous trees entering production for the first time, are more likely to produce upright vigorous branches. To promote flowering and fruiting on such branches, besides girdling, branch bending and twisting can also be carried out. The specific method is: after the autumn shoots mature, use straw or plastic bags to pull the excessively vigorous branches into a bend; when the leaf color fades from deep green to pale green, the binding can be removed. Twisting is to twist the branch once by hand from the base, injuring the bark and xylem, until the leaf color fades from deep green to pale green.
Growth Habits of Mandarin Oranges
The growth and development, flowering and fruiting of mandarin orange trees are closely related to environmental conditions such as temperature, sunlight, moisture (humidity), soil, as well as wind, altitude, topography and slope aspect. Among these conditions, temperature has the greatest influence; even a temperature difference of 0.5°C can sometimes produce completely different results. High temperatures are also unfavorable to the growth and development of mandarin oranges; when air temperature and soil temperature are above 37°C, the fruit and root system stop growing.
Mandarin oranges are a tree species with relatively strong shade tolerance, but good sunlight is still needed for high quality and high yield. Generally, areas with an annual sunshine duration of 1200-2200 hours can all grow normally. Mandarin oranges have a relatively wide adaptability to soil; purple soil, red-yellow soil, sandy beach and coastal mudflat can all support growth at pH 4.5-8, with pH 5.5-6.5 being the most suitable.
Planting Methods for Mandarin Oranges
Mandarin oranges are generally planted in February-March in spring. For developing mandarin oranges on fertile, deep paddy fields and riverside alluvial soil, shallow pits can be dug for planting, while paddy fields should be built into high beds arranged by plant and row. For barren dry land and sloping soil, deep pits 1 m square should be dug, with sufficient base fertilizer prepared; apply 3 jin of phosphate fertilizer, 5 jin of lime, 100 jin of garbage mud or pond mud, and 30-50 jin of pig, cattle and chicken manure per pit. When filling the pit, mix the fertilizer with the soil thoroughly before returning it to the pit, and build the tree tray about 20 cm above the ground. Before planting, part of the branches and leaves of the seedlings should be pruned to reduce water evaporation, the main root should be cut, and fibrous roots should be retained as much as possible.
When planting, dig a shallow pit, let the fibrous roots spread naturally, then backfill soil and compact the soil; the buried soil height must not cover the graft union. After planting, cover the tree tray with rice straw or other weeds and water thoroughly to settle the roots. Within one month after planting, keep the soil near the roots moist; when the temperature is high, there has been a long clear period without rain, and the soil is dry, water every day; on rainy days or when the soil is moist, there is just no need to water.
Fertilizer and Water Management for Mandarin Oranges
1. Fertilization principles: Fully meet the needs of blood oranges for various nutrient elements, advocate applying more organic fertilizer, and rationally apply inorganic fertilizer and formula fertilizer. Also guide fertilization according to leaf analysis results, orchard soil analysis results, blood orange phenological periods, etc.
2. Fertilization methods: Mainly soil fertilization, combined with foliar fertilization. Use methods such as ring trench application, strip trench application, hole application and spreading fertilizer on the soil surface.
3. Fertilization for young trees: Apply frequently and lightly, mainly nitrogen fertilizer, combined with phosphorus and potassium fertilizer; fertilize 5-6 times during the spring, summer and autumn shoot sprouting periods, applying 0.4 jin of ammonium bicarbonate or 0.2 jin of urea per tree each time in March, May, June, July, September and December. For 1-3 year old young trees, apply 100-400 grams of pure nitrogen per tree per year, with an N:P:K ratio of 1.0:(0.4-0.5):1.0 as suitable.
4. Fertilization for mature trees: Apply four good rounds of fertilizer to mature trees, namely budding fertilizer, fruit preservation fertilizer, fruit strengthening fertilizer and post-harvest fertilizer. The fertilization amounts are generally 2-3 jin of chemical fertilizer plus one load of manure water for budding fertilizer. 1-2 jin of phosphorus and potassium fertilizer + 1 jin of chemical fertilizer for fruit preservation fertilizer. 1-2 jin of chemical fertilizer + 1-2 jin of phosphorus and potassium fertilizer for fruit strengthening fertilizer. Post-harvest fertilizer (base fertilizer) is mainly organic fertilizer, applying 50-100 jin of organic fertilizer per tree plus 1-2 jin of chemical fertilizer.
5. Water management: Irrigate when the soil is dry and drain when there is standing water.
Actually, there are many methods for planting mandarin oranges. Perhaps every fruit grower has different planting techniques and methods, so fruit grower friends can communicate with and learn from one another; only in this way can the planting business be done better and more profit be created.