Preventing fruit drop on citrus trees

Managing Fruit Set and Preventing Fruit Drop in Citrus Trees

1. Handling Fruit Set

– To ensure good pollination, high fruit set, and reduce fruit drop, it is essential to keep the tree healthy and apply flowering support chemicals, with Boron being crucial. In addition, applying the biological preparation AH NO8 can provide balanced nutrition to the tree.
If the citrus tree’s roots are weak and prone to shock, avoid fertilizing during flowering and fruit set. Only resume fertilization when the tree is in fruiting and consider doing it in multiple small applications. – Girdling to Reduce Fruit Drop: During the fruit development phase, citrus trees may have flushes of new growth. If new growth occurs, the tree may shed fruit to redirect nutrients to the new shoots. Therefore, girdling should be done during the flush stage to minimize fruit drop. You can use growth inhibitors such as Chlormequat Chloride or Cycocel CCC, applying at a rate of 100ppm (equivalent to 1g/10 liters).

Note: During peak flowering, avoid spraying chemicals on the flowers and ensure regular watering to maintain soil moisture, but do not spray water directly onto the blooming flowers.

2. Preventing Excessive Fruit Drop:

Two Phases of Physiological Fruit Drop:

– **First Phase of Drop:** Typically occurs when the fruit is small, about the size of a pinky finger, approximately 3 weeks after fruit set. This type of drop is characterized by the fruit falling off with its stem attached. – **Second Phase of Drop:** Occurs when the fruit reaches around 3 cm in diameter, characterized by fruit dropping without its stem.
Fruit drop in citrus trees is almost inevitable. Important technical measures include applying additional fertilization and basal fertilization (about 100–200g N.P.K (20-20-15) per tree) and timely foliar feeding with AH NO8 to nourish the fruit and reduce drop, which also helps keep the fruit’s skin glossy and attractive. AH NO8 contains a balanced mix of organic nutrients suitable for this stage.

Note: In cases of heavy rainfall, fruit may turn yellow and drop significantly due to excessive fruit load, nutrient deficiency, and water shock.

• **Solution:** Regular watering, adequate basal fertilization, and immediate application of fruit nourishment products.

Fruit Care:

**For Small Fruits Up to 4-5 Months:** During this period, fruit growth is slow with frequent physiological drops, so care should include: – **Fertilization:** Apply a small amount of 100g NPK (20 – 20 – 15) per tree every 15 days and ensure regular watering. – **Foliar Application:** Remember to supplement with Boron 2-3 times by foliar spraying (every 10-15 days) to support fruit growth and minimize fruit drop. When fruit reaches 3-4 cm in diameter, begin additional foliar feeding and apply mite control treatments to prevent corky skin diseases.
For Larger Fruits: When fruit skin starts to roughen (like snake skin), and to promote rapid fruit growth without cracking, apply: – Fertilization: Approximately 200g NPK (20 – 20 – 15) + 50g KCl per tree every 15 days with regular watering. (Additional application of Humic and chelated trace elements can also be beneficial for increasing fruit yield.)

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