Fertilization Plans for 24 Economical Crops Including Tomatoes, Cucumbers, and Spinach to Help Achieve High Yields

Nowadays, more and more agricultural input companies are focusing on agrochemical services, but the skills of agrochemical service personnel vary greatly, and growers remain skeptical. The editor has briefly summarized the common fertilization management plans for 24 crops including tomatoes, cucumbers, and spinach, since crop fertilization management should follow the principles of adapting to local conditions and timing. But it is hoped that agricultural input practitioners who see this can grasp the underlying principles and apply them flexibly.

1. Tomato

Potassium is required the most, followed by nitrogen, and phosphorus the least. According to measurements, for every 1000 kg of tomatoes produced, 7.8 kg of nitrogen, 1.3 kg of phosphorus, 15.9 kg of potassium, 2.1 kg of CaO, and 0.6 kg of MgO need to be absorbed.

The order of element absorption is: potassium > nitrogen > calcium > phosphorus > magnesium.

During the peak fruiting period, nutrient absorption reaches its maximum, and fertilizer uptake during this period accounts for 50%-80% of the total absorption. After this, nutrient absorption gradually decreases. During the seedling stage, nitrogen fertilizer should be the main focus, with attention to applying phosphorus fertilizer as well, which can promote leaf area expansion and flower bud differentiation. During the full bloom stage of the first truss, nitrogen and potassium nutrition should be gradually increased.

During the peak fruiting period, on the basis of sufficient nitrogen and potassium supply, phosphorus nutrition must be increased, especially in protected cultivation, where attention should also be paid to nitrogen and potassium supply. At the same time, carbon dioxide gas fertilizer should be added, along with the combined application of medium elements and trace element fertilizers such as calcium, magnesium, boron, sulfur, and iron. This can not only increase yield but also improve quality and increase the marketable rate.

2. Cucumber

According to measurements, for every 1000 kg of cucumbers produced, 1.9-2.7 kg of N, 0.8-0.9 kg of P2O5, and 3.5-4.0 kg of K2O need to be absorbed from the soil. The absorption ratio of nitrogen, phosphorus, and potassium is 1:0.4:1.6. Cucumber requires the most potassium throughout its entire growth period, followed by nitrogen.

Within 30 days after transplanting, cucumber nitrogen uptake rises linearly, reaching maximum nitrogen uptake at the mid-growth stage. Upon entering the reproductive growth stage, cucumber's phosphorus absorption increases sharply, while nitrogen requirement slightly decreases. Cucumber absorbs potassium throughout its entire growth period, so attention should be paid to using potassium fertilizer in cucumber production.

3. Eggplant

During the mid-growth stage, potassium uptake is similar to nitrogen uptake. By the late growth stage, potassium absorption far exceeds nitrogen. Although phosphorus absorption increases somewhat in the late stage, it is much smaller compared to potassium and nitrogen. For every 1000 kg of eggplant produced, the absorption amounts of each element are: nitrogen 2.7-3.3 kg, phosphorus 0.7-0.8 kg, potassium 4.7-5.1 kg, calcium oxide 1.2 kg, and magnesium oxide 0.5 kg. The absorption ratio is approximately 3:1:1.5. The suitable fertilizer formula should be 15:10:20.

4. Celery

Celery's nutrient absorption throughout its entire growth period is consistent with the increase in biomass, and the absorption dynamics of each nutrient are basically the same, presenting an "S" shaped curve. The peak nutrient absorption period of autumn-sown celery is also during the peak vegetative growth period, that is, 68-100 days after sowing. During this period, the absorption of the five elements nitrogen, phosphorus, potassium, calcium, and magnesium accounts for more than 84% of the total absorption, with calcium and potassium reaching as high as 98.1% and 90.7% respectively.

Among these, nitrogen requirement is the highest, followed by calcium and potassium, with phosphorus and magnesium being the least. The ratio of nitrogen, phosphorus, potassium, calcium, and magnesium is approximately 9.1:1.3:5.0:7.0:1.0. Generally, for every 1000 kg of celery produced, the absorption amounts of nitrogen, phosphorus, and potassium are 2.0 kg, 0.93 kg, and 3.88 kg respectively.

5. Spinach

Producing 1000 kg of spinach requires 1.6 kg of pure nitrogen, 0.83 kg of phosphorus pentoxide, and 1.8 kg of potassium oxide. A relatively large amount of nitrogen fertilizer is needed to promote leaf cluster growth. In terms of nitrogen fertilizer type, application rate, and timing, spinach is a typical vegetable that prefers nitrate nitrogen fertilizer. When the ratio of nitrate nitrogen to ammonium nitrogen is above 2:1, the yield is higher. However, applying only ammonium nitrogen fertilizer will inhibit the absorption of K and Ca, causing ammonia toxicity that affects its growth.

On the other hand, applying only nitrate nitrogen fertilizer, although the plant growth volume is large, consumes too much energy during the reduction process; under weak light, nitrate nitrogen absorption may be inhibited, causing insufficient nitrogen supply.

6. Melon

Melon has a relatively short growth period and requires less fertilizer. For every 1000 kg of melon produced, approximately 3.5 kg of nitrogen, 1.72 kg of phosphorus, and 6.88 kg of potassium need to be absorbed. Calculated based on fertilizer utilization rate, the ratio of the three elements in actual fertilization should preferably be 1:1:1.

7. Pepper

Pepper is a vegetable that requires a relatively large amount of fertilizer. For every 1000 kg produced, approximately 3.5-5.4 kg of nitrogen (N), 0.8-1.3 kg of phosphorus pentoxide (P2O5), and 5.5-7.2 kg of potassium oxide (K2O) are needed.

From the early growth stage to the fruit harvest stage, the amounts of nitrogen, phosphorus, potassium, and other nutrients absorbed by pepper vary across different growth stages: from emergence to bud appearance, the plant has few roots and small leaves, requiring less nutrients, accounting for about 5% of total absorption; from bud appearance to initial flowering, the plant grows faster and expands rapidly, with increased nutrient absorption, accounting for about 11% of total absorption;

From initial flowering to full flowering and fruiting is the period of vigorous vegetative and reproductive growth for pepper, with nutrient absorption accounting for about 34% of total absorption, and it is the period of greatest nitrogen absorption; from full flowering to maturity, the plant's vegetative growth weakens, with nutrient absorption accounting for about 50% of total absorption, and this is when the demand for phosphorus and potassium is greatest; after mature fruit harvest, in order to promptly promote the growth and development of branches and leaves, a large amount of nitrogen fertilizer is needed again.

8. Ginger

For every 1000 kg of fresh ginger produced, 6.34 kg of pure nitrogen, 1.6 kg of phosphorus pentoxide, and 9.27 kg of potassium oxide need to be absorbed. The order of nutrient absorption is potassium > nitrogen > phosphorus. There are two peak periods of nutrient demand: the first is the three-branch stage, and the second is the rhizome expansion stage after the Beginning of Autumn. Fertilization principles: apply heavy organic fertilizer as base fertilizer, combined with a certain amount of compound fertilizer; for topdressing, mainly use compound fertilizer with a reasonable nitrogen-phosphorus-potassium ratio.

9. Chinese Cabbage

For every 5000 kg of Chinese cabbage produced per mu, 11 kg of pure nitrogen (N), 54.7 kg of pure phosphorus (P2O5), and 12.5 kg of pure potassium (K2O) need to be absorbed from the soil, with a ratio of 1:0.4:1.1. During the vegetative growth period of Chinese cabbage, sufficient nitrogen nutrition plays a particularly important role in promoting the formation of large green leaves and improving photosynthetic efficiency.

Due to differences in growth volume and growth rate at different growth stages, Chinese cabbage has different requirements for nutritional conditions. The overall fertilizer requirement characteristics are: nutrient absorption is low at the seedling stage, with nitrogen, phosphorus, and potassium absorption accounting for less than 10% of total absorption; it increases significantly at the rosette stage, accounting for about 30% of the total; nutrient absorption is highest at the heading stage, accounting for about 60% of the total.

10. Yam

For every 1000 kg of tubers produced, 4.32 kg of pure nitrogen, 1.07 kg of phosphorus pentoxide, and 5.38 kg of potassium oxide are needed. The required ratio of nitrogen, phosphorus, and potassium is 4:1:5. The amount and type of fertilizer needed vary across different growth stages. Seedling stage: plant growth volume is small, and the absorption of nitrogen, phosphorus, and potassium is also low.

Peak branch and leaf growth stage: as the plant growth rate accelerates and growth volume increases, nutrient absorption also increases, especially nitrogen absorption which increases considerably. Rapid tuber expansion stage: stem and leaf growth reaches its peak, tubers grow and expand rapidly, and the absorption of nitrogen, phosphorus, and potassium also reaches its peak.

11. Potato

Potato is a tuber crop. For every 1000 kg of fresh tubers produced, 4.4 kg of nitrogen, 1.8 kg of phosphorus, and 7.9 kg of potassium are needed. It is a typical potassium-loving crop, and the yield-increasing effect on the crop is potassium > nitrogen > phosphorus. Potato has a short growth period and high yield, requiring a large amount of base fertilizer.

12. Welsh Onion

The yield of Welsh onion depends on the length and thickness of the false stem. The growth of the false stem is in turn affected by leaf emergence speed, leaf number, and leaf area size. Its internal factors are constrained by variety characteristics and premature bolting, while its external factors are comprehensively affected by temperature, moisture, light, and soil nutrition.

Generally, the more leaves, the taller and thicker the false stem; the more vigorous the leaf blade growth, the thicker the leaf sheath, and the thicker the false stem. Welsh onion is a biennial cold-resistant vegetable, and its entire growth period is divided into two phases: vegetative growth and reproductive growth. From the appearance of the first true leaf to overwintering is the seedling stage, lasting 40-50 days. During this period, temperatures are relatively low, growth volume is small, and management focuses on preventing seedling spindling and ensuring safe overwintering, so fertilizer requirement is very low.

From the Beginning of Spring when it turns green to transplanting is the vigorous seedling growth period, lasting 80-100 days. This is the critical period for cultivating strong seedlings, and "seedling-promoting fertilizer" should be applied in a timely manner, mainly with quick-acting nitrogen fertilizer. Around White Dew is the most suitable growing season for Welsh onion, entering the peak period of white stalk formation, when the false stem rapidly elongates and thickens. This period is another critical time for fertilizer and water management.

Since Welsh onion is a heavy feeder, on the basis of applying sufficient base fertilizer, topdressing should be carried out according to the fertilizer requirement patterns of each growth stage. Base fertilizer should mainly be organic fertilizer, requiring complete nitrogen, phosphorus, and potassium, with special attention to the application of sulfur fertilizer. Topdressing should mainly be quick-acting nitrogen fertilizer, following the principle of "light early, heavy later, focus on the middle and supplement the end." For every 1000 kg of Welsh onion produced, approximately 3.4 kg of nitrogen, 1.8 kg of phosphorus, and 6.0 kg of potassium are absorbed, with a ratio of 1.9:1:3.3.

13. Garlic

Garlic is a crop that loves potassium and sulfur. During garlic growth, the demand for nitrogen, phosphorus, and potassium nutrients is higher for nitrogen and potassium, and lower for phosphorus. Generally, the yield per mu of fresh garlic is 1500-2500 kg. Experiments have shown that for every 1000 kg of garlic bulbs produced, approximately 4.8 kg of nitrogen, 1.4 kg of phosphorus, 4.4 kg of potassium, and 0.8 kg of sulfur need to be absorbed; during the garlic growth cycle, the period from garlic scape growth to garlic bulb expansion is its peak fertilizer demand period.

14. Chinese Chive

Chinese chive has a very strong tolerance to fertilizer, and its fertilizer requirement varies with age. Chinese chive sown in the current year, especially during the germination and seedling stages, consumes little fertilizer, while 2-4 year old Chinese chive has a larger growth volume and requires more fertilizer. Generally, for every 1000 kg of Chinese chive produced, 1.5-1.8 kg of N, 0.5-0.6 kg of P, and 1.7-2.0 kg of K are needed.

15. Taro

Among the three essential fertilizer elements, potassium is required the most, followed by nitrogen fertilizer, and phosphorus fertilizer the least. Generally, the nitrogen:phosphorus:potassium ratio for taro cultivation is 2:1:2.

16. Carrot

For every 1000 kg of carrots produced, 2.4-4.3 kg of nitrogen, 0.7-1.7 kg of phosphorus, and 5.7-11.7 kg of potassium are needed. Its fertilizer absorption pattern is as follows: slow in the early growth stage, and rapid growth increase when the root system begins to expand in the mid-to-late stage, with nutrient absorption also increasing along with the increase in growth volume.

Within two months after sowing, the absorption of each element is not large. As the root expands, absorption increases significantly, with potassium being absorbed the most, followed by nitrogen, calcium, phosphorus, and magnesium in decreasing order. At harvest, potassium is the highest in leaves, followed by nitrogen, calcium, and magnesium, with very little phosphorus. In the roots, potassium and nitrogen are the highest, followed by phosphorus, calcium, and magnesium.

Carrot's nitrogen requirement is mainly in the early stage. Within 30-50 days after sowing, appropriate topdressing of nitrogen fertilizer is very necessary. If nitrogen is deficient during this period, the root diameter will noticeably decrease, and fleshy root expansion will be poor. Different forms of nitrogen have a great impact on carrot growth. Carrot absorbs relatively little phosphorus, about 1/3 of its nitrogen uptake.

When the available phosphorus content in the soil is low, the effect of increasing phosphorus fertilizer application is obvious, and as the application rate increases, yield also tends to increase. For calcareous soils with a relatively large phosphorus absorption coefficient, applying more phosphorus fertilizer as base fertilizer is beneficial for early plant growth and later root expansion. Potassium's main effect on carrot is to promote fleshy root expansion. In production, attention should be paid to the application of potassium fertilizer to prevent soil potassium deficiency, especially during the fleshy root expansion period, where potassium supply must be ensured.

17. Radish

For every 1000 kg of radish produced, 2.1-3.1 kg of N, 0.8-1.9 kg of P2O5, and 3.8-5.6 kg of K2O need to be absorbed from the soil. The ratio of the three is 1:0.2:1.8. It can be seen that radish is a potassium-loving vegetable and should not be given excessive nitrogen fertilizer.

In addition, radish is relatively sensitive to boron. Foliar spraying of boron fertilizer during the early and peak stages of fleshy root expansion can effectively improve radish quality.

18. Loofah

Loofah grows fast, bears many fruits, and loves fertilizer, but its root system is shallow. It has weak fertilizer absorption and tolerance, and requires loose, fertile soil rich in organic matter. According to measurements, for every 1000 kg of loofah produced, 1.9-2.7 kg of nitrogen, 0.8-0.9 kg of phosphorus, and 3.5-4.0 kg of potassium need to be absorbed from the soil.

Within 30 days after transplanting, loofah nitrogen uptake shows a linear upward trend, with maximum nitrogen uptake at the mid-growth stage. Upon entering the reproductive growth stage, the demand for phosphorus increases sharply, while the demand for nitrogen slightly decreases. Before the fruiting stage, the weight gain of various plant organs is slow, and the flow of nutrients is mainly to roots and leaves, providing nutrients for vine elongation and flower bud differentiation and development.

After entering the fruiting stage, the plant's growth volume increases significantly, reaching its maximum at the peak fruiting stage. During the peak fruiting stage, loofah's absorption of nitrogen, phosphorus, and potassium accounts for approximately 50%, 47%, and 48% of total nitrogen, phosphorus, and potassium absorption respectively. By the late fruiting stage, growth rate slows down and nutrient absorption decreases, with nitrogen and potassium decreasing more noticeably.

19. Common Bean

Nitrogen: Common bean prefers nitrate nitrogen fertilizer. More nitrogen supply is not necessarily better. Appropriate nitrogen application helps increase yield and improve quality, but excessive application can cause flower drop and delayed maturity, affecting common bean yield and profitability. Phosphorus: Phosphorus plays an important role in the formation of common bean rhizobia and in flowering and pod setting.

Phosphorus deficiency easily leads to poor growth and development of common bean plants and rhizobia, reduced number of flowers and pods, fewer seeds per pod, and reduced yield. Potassium: Potassium can significantly affect the growth and development of common bean and yield formation. Insufficient potassium fertilizer supply can reduce common bean yield by more than 20%. In production, with appropriately more nitrogen fertilizer, even if potassium application is somewhat less, potassium deficiency symptoms generally will not appear.

Magnesium: Common bean is prone to magnesium deficiency. If magnesium in the soil is insufficient, starting 1 month after sowing, yellowing and chlorosis begins first in the primary leaves, then between the veins of the first true leaf, gradually developing toward upper leaves, lasting about 7 days, after which leaves begin to drop and yield decreases. Molybdenum: The trace element molybdenum is an important component of nitrogenase and nitrate reductase. In physiological metabolism, it mainly participates in biological nitrogen fixation and promotes nitrogen and phosphorus nutritional metabolism in the plant.

20. Pumpkin

Pumpkin has different nutrient absorption amounts and ratios at different growth and development stages. The seedling stage requires less fertilizer. Entering the fruit expansion stage is the period of greatest fertilizer demand, especially with a sharp increase in nitrogen absorption. Potassium also shows a similar trend, while phosphorus absorption increases less.

According to research from Miyazaki, Japan, during the 137 days from transplanting to vine removal, pumpkin's absorption of the five elements (nitrogen, phosphorus, potassium, calcium, magnesium) increases slowly in the first 1/3 of the time, grows rapidly in the middle 1/3, and increases most significantly in the last 1/3. Throughout the entire period, potassium and nitrogen are absorbed the most among the five elements, calcium is in the middle, and magnesium and phosphorus are the least.

The increase in yield is completely consistent with the overall trend of absorption of the five elements, also rising rapidly during the last 1/3 of the time. Producing 1000 kg of pumpkin requires absorption of 3.5-5.5 kg of nitrogen (N), 1.5-2.2 kg of phosphorus (P2O5), and 5.3-7.29 kg of potassium (K2O). Pumpkin responds well to organic fertilizers such as barnyard manure and compost.

21. Cherry

Cherry's leaf expansion, shoot growth, flowering, and fruit development to maturity are all concentrated in the first half of the growing season. From flowering to fruit maturity takes only about 45 days, and flower bud differentiation is basically completed within 1-2 months after fruit harvest. Therefore, cherry has the characteristics of rapid growth and development and concentrated fertilizer demand. During the year, fertilizer demand is greatest from the leaf expansion stage to before fruit maturity, followed by the peak flower bud differentiation period after fruit harvest, and relatively low during the rest of the time. In production, fertilization before winter, during the flowering period, and after fruit harvest must be well managed, as these are important measures for increasing yield and improving quality.

22. Sweet Potato

Sweet potato's economic product is the underground storage root. According to research, for every 1000 kg of fresh tubers produced, 4.9-5.0 kg of nitrogen (N), 1.3-2.0 kg of phosphorus (P2O5), and 10.5-12.0 kg of potassium (K2O) are needed. The ratio of nitrogen, phosphorus, and potassium is approximately 1:0.3:2.1. Throughout its life, sweet potato's demand for the three elements nitrogen, phosphorus, and potassium is highest for potassium, followed by nitrogen, and lowest for phosphorus. The trend of water and nutrient absorption from the soil is also roughly the same. During the entire growth process of sweet potato, the amounts and rates of nitrogen, phosphorus, and potassium absorption differ significantly across different growth stages.

Nitrogen absorption is fast and high in the early and mid-growth stages, mainly used for stem and leaf growth. Nitrogen absorption and utilization reach their peak during the peak stem and leaf growth period. In the late stage, stems and leaves decline, tubers expand rapidly, nitrogen absorption slows down, and demand decreases. Phosphorus absorption and utilization gradually increase with stem and leaf growth, reaching their peak during the tuber expansion period. Potassium absorption and utilization are higher than nitrogen and phosphorus from the beginning of growth to harvest.

As leaves and vines grow, potassium absorption gradually increases. When aboveground parts gradually slow from peak growth, the leaf area coefficient begins to decline, stem and leaf weight gradually decreases, and during the rapid tuber expansion period, a large amount of potassium is particularly needed. The overall trend of sweet potato's demand for nitrogen, phosphorus, and potassium is rapid absorption in the early and mid-stages and slow absorption in the late stage.

Although sweet potato's absorption of essential trace elements throughout its life is very small, if the soil is deficient, normal growth will be seriously affected. When soil available zinc content is below 0.5 mg/kg, sweet potato leaves become pale, leaves become small, branching decreases, and drought resistance decreases. Or when leaf magnesium content is below 0.05%, magnesium deficiency symptoms such as small leaves curling upward and yellowing between veins of old leaves appear. Therefore, in production, close attention must also be paid to the dynamic changes in trace element content in the soil, and if deficient, timely supplementation is needed.

23. Grape

Although grape is a vine fruit tree, it has a well-developed root system, many vines and large leaves, strong polarity, vigorous growth, abundant fruit and high yield, and a long lifespan. Its fertilizer requirement characteristics:

First, it requires many elements. According to experiments and production verification, its essential elements are 16 kinds including carbon, hydrogen, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, boron, manganese, copper, zinc, molybdenum, and chlorine. If one of them is lacking or insufficient, normal physiological activities will be affected. It cannot be replaced by other elements, and only by applying the deficient element can it be corrected; otherwise, it will lead to deficiency symptoms and cause physiological disorders.

Second, fertilizer demand is large. According to experiments, for every 100 kg of fruit produced, 300 g of pure nitrogen, 150 g of pure phosphorus, and 360 g of pure potassium are needed. Adding the nutrients needed for root, vine, shoot, and leaf growth and losses and fixation, a high-yield orchard producing 2000 kg per 667 sq m needs to apply 12.5-15.0 kg of pure nitrogen, 10-12.5 kg of pure phosphorus, and 10.0-15.0 kg of pure potassium per 667 sq m each year. The ratio of nitrogen, phosphorus, and potassium is approximately 10:5:12.

Third, potassium demand is large. Grape is a famous "potassium plant," requiring a large amount of potassium throughout its entire growth period, with its requirement ranking first among the three essential elements. If potassium is lacking or insufficient, leaves cannot manufacture starch and fatty acids, nitrate nitrogen increases, leaves become fewer and smaller, leaf margins scorch, new shoots decrease, fruit stalks turn brown, berries shrink or crack, coloring is poor, sugar is low and taste is sour, quality is poor, and the plant's cold and drought resistance is weak.

Fourth, the elements and amounts required differ across various growth and development stages throughout the year. From bud break and flowering to the early young fruit stage, nitrogen is needed the most, accounting for about 64.5% of the annual requirement. Phosphorus absorption gradually increases with branch and leaf growth, flowering and fruit setting, and fruit enlargement, reaching its peak at the peak new shoot growth stage and berry enlargement stage.

Although potassium absorption begins from leaf expansion and shoot growth, the greatest potassium demand is from fruit enlargement to the coloring stage. If potassium is insufficient during this period, the fruit will have poor color, low sugar, and sour taste, and in severe cases may even fail to mature.

24. Cotton

Cotton's normal growth and development go through stages such as the seedling stage, bud stage, flowering and boll stage, and boll opening stage. Generally, for every 667 sq m producing 100 kg of lint cotton, 7-8 kg of nitrogen, 4-6 kg of phosphorus, and 7-15 kg of potassium need to be absorbed.

For every 667 sq m producing 200 kg of lint cotton, 20-35 kg of nitrogen, 7-12 kg of phosphorus, and 25-35 kg of potassium need to be absorbed.