SOUTHERN FERTILIZER FOR COFFEE PLANTS IN THE RAINY SEASON

1. Coffee trees and their growth requirements

When coffee trees reach maturity, they begin to flower and bear fruit. During the reproductive growth stage, coffee needs a lot of nutrients to differentiate flower buds and then to support fruit development. In the southern region of our country, nutrients are usually supplemented in the middle and at the end of the dry season (dry-season fertilization). However, this amount of nutrients can only ensure a short growth period for flower bud differentiation. In the rainy season, coffee requires a large amount of nutrients to meet the tree’s needs for fruit development.

When coffee enters the flowering and fruiting stage, it is also called the business/production stage. According to some studies, in a one-year fruiting growth cycle, with an average yield of 3 tons of green coffee beans/ha, coffee trees remove about 123 kg N; 16 kg P₂O₅; 150 kg K₂O and many other secondary and micronutrients. Fertilizer is applied to the soil to supply nutrients to coffee trees. Many documents state that the efficiency of nutrient use by the plant only reaches about half of the (pure) amount applied, and may even be as low as 20–25% in the case of phosphate fertilizer. This is due to the influence of many soil factors and crop characteristics. Therefore, depending on the soil type, we need to estimate and compensate for the loss during plant uptake. Following the recommendations for using Phân bón Miền Nam (Southern Fertilizer) products will help increase fertilizer use efficiency in coffee.

2. Southern Fertilizer for coffee in the rainy season

In this reproductive growth stage, the plant’s demand for potassium and nitrogen is higher than for phosphorus. In addition, coffee also needs a considerable amount of secondary and micronutrients.

– At the beginning of the rainy season, at least 5–7 days before applying chemical fertilizer, use SFJC Bio-Gold G.A.P organic fertilizer. When applying, make a 10–15 cm furrow around the edge of the canopy; apply the fertilizer and cover it with soil around the basin, and if possible irrigate afterward. Dosage: 0.7–1 kg/tree.

* SFJC Bio-Gold G.A.P organic fertilizer is a product of Southern Fertilizer Joint Stock Company, a clean fertilizer made from 100% plant-based materials, suitable for G.A.P cultivation. It contains 55% organic matter, naturally derived total nitrogen, humic acid, fulvic acid, Trichoderma fungi, etc. It helps create a stable soil ecosystem, enhances the effectiveness of beneficial microorganisms, restricts harmful fungi, reduces nutrient leaching, stimulates the formation of more young roots, helps crops develop a stronger root system, and at the same time limits soil degradation and loss of soil fertility.

– At the beginning of the rainy season, around May–June (solar calendar): Use Southern Fertilizer NPK 16-16-8-6S+TE or Southern Fertilizer NPK 16-8-16+5S+TE. Dosage: 0.4–0.5 kg/tree.

* Southern Fertilizer NPK 16-16-8-6S+TE and Southern Fertilizer NPK 16-8-16+5S+TE are NPK products produced on a modern rotary drum steam granulation line. These formulas meet the nutritional needs of coffee during the early rainy-season fruit development stage. Depending on soil characteristics and tree vigor, they can be selected accordingly. On clayey soils or when the leaves appear pale green, Southern Fertilizer NPK 16-16-8+6S+TE should be used. For trees with normal growth, Southern Fertilizer NPK 16-8-16+5S+TE is recommended.

– In the middle of the rainy season, around July–August (solar calendar): Use Southern Fertilizer NPK 17-7-17+TE or Southern Fertilizer NPK 18-5-18+4S+TE. Dosage: 0.6–0.7 kg/tree. These products are also produced using the rotary drum steam granulation system mentioned above. At this stage, the nutrient demand of coffee is higher. Therefore, these two NPK formulas have higher nutrient content and are applied at higher rates, helping coffee develop the largest possible fruit size. Since the two products are similar, either one can be used.

– At the late rainy season, around August–September (solar calendar): Use Southern Fertilizer NPK 17-5-19+3S+TE or Southern Fertilizer NPK 16-5-20+4S+TE. Dosage: 0.5–0.6 kg/tree. In this final application, the nitrogen and potassium contents differ from each other. Potassium plays a role in enhancing metabolism and increasing stress tolerance; it helps coffee beans at this stage become firmer, thereby increasing the yield of green coffee and improving the proportion of high-grade beans. Depending on soil conditions and farming practices, one of these two products can be used.

– In the early season, when preparing for flower bud differentiation and early fruit development, foliar fertilizers Yogen Mitsuivina such as Yogen 32 and Yogen No4 can be used to help improve fruit set and support fruit growth.

3. Pest and disease control

– Some common pests and diseases in the rainy season:

+ Insect pests: Mealybugs (Pseudococus spp.); Branch borer (Xyleborus morstatti); Aphids, brown scale, green scale; Pink coffee borer (Zeuzera coffeara); White stem borer (Xylotrechus quadripes); Nematodes;

+ Diseases: Dieback and fruit rot (Colletotrichum spp.); Coffee leaf rust (Hemileia vastatrix); Pink disease (Corticium salmonicolor); Collar rot (Fusarium spp.); Stem canker/rot (Fusarium spp.); Yellow leaf and fruit drop disease on coffee;

Dieback, fruit rot, pink disease, yellowing leaves, nematodes, fungi, cicada nymphs, branch borers, fruit borers, and mealybugs are all causes of severe yellowing leaves and massive fruit drop in coffee. Integrated pest management measures should be used to reduce and control these problems.

– Cultivation measures:

+ Prune water sprouts, branches inside the canopy, weak and excess branches to concentrate nutrients on fruit development. Prune dry, old and pest-infested branches to keep the plantation airy, helping trees grow well, increasing resistance to pests and diseases, and limiting the spread of diseases that cause fruit drop.

+ Field sanitation: Regularly collect diseased branches, leaves, flowers and fruits, dry them and burn them to prevent the development of inoculum sources.

– Apply fertilizers in a balanced and appropriate manner.

– Chemical control measures (according to recommendations and products listed in the approved registry).

When coffee trees show signs of pest or disease damage, consult agronomy experts to select the right control measures for each specific pest or disease in order to achieve the best effectiveness.

Collected and compiled by

Lê Minh Giang