What are the correct methods for watering and fertilizing apple trees?
How do you water and fertilize apple trees when planting? What watering and fertilizing methods give good results? We would also like experienced readers to share their advice. Watering and fertilizing apple trees are closely linked to apple quality and yield, so Zhongdi Network has put together the watering methods and fertilizing methods for apple trees, listed in detail below...
How do you water and fertilize apple trees when planting? What watering and fertilizing methods give good results? We would also like experienced readers to share their advice.Watering and fertilizing apple trees are closely linked to apple quality and yield, so Zhongdi Network has put together the watering methods and fertilizing methods for apple trees, listed in detail below for readers' reference.
Method 1. Using surface irrigation:
Surface irrigation generally means flood irrigation and long-border flow irrigation, but surface irrigation wastes a lot of water. Especially where grass grows in the orchard, the water flow is blocked by the grass, and the amount of irrigation varies greatly between sections at different distances from the water source. Therefore, apple orchards had best not use flood irrigation or long-border flow irrigation, and should instead adopt the following water-saving surface irrigation methods.
1. Small-border irrigation: one border per fruit tree, or one border for 2 to 4 fruit trees; the smaller the border, the more water is saved. Small-border irrigation requires building main canals, branch canals and lateral canals, which interferes with mechanized orchard operations, so it suits small orchards under household contract management. Soft plastic pipes can also replace branch canals and lateral canals; the original channels can be slightly raised so that machinery can travel over them, overcoming the drawback of many border ridges and canal ridges interfering with mechanized operations, and it saves water, so it is worth promoting. However, the soft pipe must be connected to a tap with a certain amount of pressure. Some orchards share one water supply system with pipeline spraying, which is also very convenient.
2. Trickle furrow irrigation: that is, when irrigating temporarily between rows, machinery opens several furrows and water is run through them. Open the furrow and irrigate as you go, and cover the soil promptly to conserve moisture.
Method 2. Using drip irrigation:
So-called drip irrigation is short for drip watering. At the water source the water is filtered and pressurized, then delivered through a piping system to beneath the canopy of each fruit tree, where several drippers let the water drip into the soil drop by drop, evenly and slowly. Once the water source is turned on, all drippers drip and irrigate simultaneously and in equal amounts. This method of water supply keeps the soil around the fruit tree roots moist while keeping the soil between trees and rows relatively dry.
Drip irrigation has many advantages: it saves water, using 1/2 the amount of sprinkler irrigation and 1/3 or even less of surface flood irrigation; it does not require land preparation; fruit trees grow and bear fruit well, with high yield and excellent quality; and it saves labor in management and is highly efficient. Drip irrigation requires relatively high material investment and has strict water quality requirements, which are the limiting factors for its large-scale promotion at present.
Method 3. Using sprinkler irrigation:
Sprinkler irrigation generally means spraying water for irrigation. A water pump and piping system are used to spray water under a certain pressure through sprinkler heads into the air, where it breaks into fine droplets and irrigates like rain.
The advantages of sprinkler irrigation are also that it saves water, does not require land preparation, gives high fruit yield and excellent quality, and has high irrigation efficiency; sprinkler irrigation also helps improve the orchard microclimate. Sprinkler irrigation also requires a relatively high material investment at the outset, and in windy areas its irrigation efficiency is affected to some extent.
According to the height of the sprinkler heads on the risers, sprinkler irrigation has three forms: one is where the sprinkler heads are above the canopy, each head controls a relatively large irrigation area, and high-pressure heads are mostly used; one is where the sprinkler heads are in the middle of the canopy, each head controls only part of the irrigation area of the 4 adjacent trees, and medium-pressure heads are used; and another is where the sprinkler heads are below the canopy, one tree needs several small sprinkler heads, and each head controls a very small irrigation area. This low sprinkler irrigation is also called micro-sprinkling and uses only low-pressure heads. Micro-sprinkling is generally unaffected by wind and saves more water than medium- and high-level sprinkler irrigation.
Method 4. Using fertigation:
Fertigation generally means a method of fertilizing an orchard by applying fertilizer through the irrigation system (sprinkler irrigation, micro-irrigation, drip irrigation).
The characteristics and benefits of fertigation:1. The fertilizer elements are already in dissolved form, so they can be absorbed and used by the roots more quickly than fertilizer applied directly to the soil surface, improving fertilizer use efficiency. According to reports from Australia, compared with surface irrigation, drip fertigation can save fertilizer (nitrogen fertilizer) by 44% to
57%, and sprinkler fertigation can save 11% to 29%.
2. The irrigation period is highly flexible and can be arranged entirely according to the needs of the fruit trees.
3. Nutrients are evenly distributed in the soil, which neither damages the roots nor affects the soil structure of the tilled layer.
4. It can save the cost and labor of fertilizing. Fertigation is especially suitable for mature orchards with interlocking canopies and for densely planted orchards. According to foreign reports, drip fertigation with nitrogen or with nitrogen-phosphorus-potassium fertilizer has good effects on young sweet orange trees. Some trials show that in micro-irrigation fertigation, the acid content of the fruit decreases markedly, while the effects on fruit yield, size and quality do not differ noticeably from those of direct fertilizer application.
Issues to note in fertigation:1. Clogging of sprinkler heads or drip heads is an important problem in fertigation, so soluble fertilizers must be used.
2. When two or more fertilizers are mixed and applied, chemical reactions between them must be prevented so that insoluble compounds are not formed; for example, mixing magnesium nitrate with phosphorus or ammonia fertilizer will form insoluble magnesium ammonium phosphate.
3. The pH of the water used in fertigation should preferably be neutral. For example, strongly alkaline water can react with phosphorus to form insoluble calcium phosphate, which reduces the availability of various metal elements and seriously affects the application results.
Fertilizer amounts for apple trees:
Base fertilizer amount for apple trees: Practice at various plantations shows that if the base fertilizer amount for apple trees is calculated by tree age, for each additional year, the amount of organic fertilizer applied should increase by 15 kg. If calculated by yield, when the yield is below 22500 kg/hectare, apply 1.5 kg of organic fertilizer per 1 kg of fruit; when the yield is above 22500 kg/hectare, apply 2.5 kg of organic fertilizer per 1 kg of fruit. The base fertilizer amount should account for more than 70% of the total annual fertilizer application. When applying it, according to the balanced fertilization requirements for high quality and high yield, appropriately combine it with phosphorus, potassium and trace element fertilizers.
Topdressing amount for apple trees: Experience suggests that for every 100 kg of fruit produced, 0.8-1 kg of pure nitrogen is needed, roughly equivalent to 2 kg of urea. The general ratio of nitrogen:phosphorus:potassium is preferably 1:0.5:1, with certain adjustments according to different soils, tree vigor and cultivation methods.
Root topdressing for apple trees: The topdressing periods, types and doses commonly used for apple trees. It can be seen that in the early part of the growing season, nitrogen is mainly applied, and the urea concentration should preferably be 0.3%-0.4%; in the latter half of the growing season, phosphorus and potassium are mainly applied, and the potassium dihydrogen phosphate concentration should preferably be 0.3%-0.5%, while urea can be 0.5%-0.7%.
Watering periods and irrigation amounts for apple trees:
Because China's main apple-producing areas are in the semi-arid northern regions, with annual rainfall between 550 and 750 mm, and the seasonal distribution within the year is unreasonable, mainly because rainfall is very scarce during the long 8 to 9 months from late autumn to early summer, soil and atmospheric drought is severe. The early stage of spring shoot growth in apples coincides with fruit set and the young fruit stage, which is the critical period for water demand, that is, the key water-demand period.
The best watering periods for apple trees: if watering twice a year, one should be at the fruit-setting stage after petal fall, and one at late autumn to early winter (freezing water); if irrigating three times a year, one can be added 4 to 6 weeks after the first irrigation. In spring, before bloom and during bloom, irrigate as little as possible to avoid lowering soil temperature and affecting fruit set. After irrigation in late autumn to early winter, there should be good moisture-conservation measures, so that this watering can last until spring and still have an effect.
The irrigation amount for apple trees is considered from the standpoint that a certain degree of drought is favorable to fruit tree growth and fruiting and from water conservation, and it is mainly based on soil moisture content. The soil moisture content suitable for apple tree growth is 60%-80% of field maximum water-holding capacity, with 60% as the lower limit. Soils of different textures differ greatly in field water-holding capacity (the percentage of water in the dry weight of the soil): clay is about 45%, clay loam 40%, sandy loam 28%, and sandy soil only 5%-8%. The minimum irrigation amount should bring the moisture of the 50-100 cm soil layer to more than 60% of maximum field water-holding capacity, and this should be maintained for a certain period.
When the water in the soil decreases to the point where it cannot move, it also becomes difficult for plants to absorb and use soil water; the soil moisture content at this time is called the moisture equivalent. The irrigation amount for several soils near the moisture equivalent can serve as the orchard minimum, and the most ideal irrigation amount is shown in the table for reference. Generally, the irrigation amount before the rainy season should not be large, while during drought after the rainy season it should be larger.
Methods for identifying orchard soil moisture content:
When the soil type is fine sandy soil or sandy loam, if the soil feels dry in the hand with no cool sensation, the soil moisture content is 3%-4%, which is dry moisture; if the soil feels slightly moist in the hand, the soil moisture content is 6%-8%, which is gray moisture; if the soil feels clearly moist in the hand, the soil moisture content is 10%-12%, which is yellow moisture; if the soil can be formed into a ball in the hand and leaves wet traces on the hand, the soil moisture content is 14%-16%, which is brown moisture; if water can be squeezed out when the soil is held in the hand, the soil moisture content is
18%-20%, which is black moisture.
When the soil type is light loam or medium loam, if the soil feels dry in the hand with no cool sensation, the soil moisture content is 4%-6%, which is dry moisture; if the soil feels slightly moist in the hand, the soil moisture content is 8%-10%, which is gray moisture; if the soil feels clearly moist in the hand, the soil moisture content is 12%-14%, which is yellow moisture; if the soil can be formed into a ball in the hand and leaves wet traces on the hand, the soil moisture content is 16%-18%, which is brown moisture; if water can be squeezed out when the soil is held in the hand, the soil moisture content is 20%-22%, which is black moisture.
When the soil type is heavy loam or clay, if the soil feels dry in the hand with no cool sensation, the soil moisture content is 6%-8%, which is dry moisture; if the soil feels slightly moist in the hand, the soil moisture content is 10%-12%, which is gray moisture; if the soil feels clearly moist in the hand, the soil moisture content is 14%-16%, which is yellow moisture; if the soil can be formed into a ball in the hand and leaves wet traces on the hand, the soil moisture content is 18%-20%, which is brown moisture; if water can be squeezed out when the soil is held in the hand, the soil moisture content is 22%-24%, which is black moisture.
Temperature requirements for apple tree growth
Fertilizing methods for apple trees