Sugar orange flower promotion techniques: when to promote flowering, how to promote flowering, and whether girdling is needed

Sugar orange is currently one of the more widely planted citrus varieties. It generally flowers and bears fruit in the second year after planting, with high yield and warmth, and relatively high economic value. However, because excessive tree vigor or failure to bloom, or late blooming, affects yield, timely flower promotion measures must be taken to achieve high and stable yields. Let's take a look at the details below. The spring shoot stage of sugar orange is also the stage when spring roots develop heavily and flower promotion begins.

1. Root pruning

Sugar orange absorbs nutrients and water from the soil through its root system to maintain growth. When excessive tree vigor affects normal flowering, we can adopt root pruning measures to reduce the absorptive capacity of the root system, decrease the plant's absorption of water and nutrients, thereby inhibiting vegetative growth and prompting the plant to shift to reproductive growth. This method works better for plants with relatively strong tree vigor. Root pruning is generally carried out from September to December. First, dig a trench 50 cm wide and 30 cm high within the canopy; the extent depends on the canopy. Leave the roots exposed for 1 month, then cover with soil. However, this method is suitable for areas with relatively high winter temperatures and no frost damage.

2. Girdling

Girdling is a measure used in production. It can prevent nutrients in the tree from flowing downward, promote the accumulation of nutrients in the upper part, promote flower bud differentiation, and make the plant bloom more. The timing of girdling depends on local climatic conditions, generally from October to November. Use a specially made girdling knife to cut through the phloem of the branch, with the depth reaching the xylem but without damaging the xylem. After girdling, pay attention to fertilizer and water management, do a good job of disinfecting the wounds, and also note that strong pesticides such as lime sulfur mixture should not be sprayed, so as to avoid the wounds failing to heal normally and causing later flower and leaf drop.

3. Chemical regulation

According to modern research, the differentiation of sugar orange is related to its hormonal regulation. Therefore, during flower bud differentiation of sugar orange, spraying a higher concentration of gibberellin will inhibit its flower bud differentiation, while a lower concentration will promote flowering. So in production, paclobutrazol is often sprayed. Generally, from August to December, for plantings with relatively strong tree vigor, spray paclobutrazol once every half month for 2-3 consecutive times. Of course, it can also be applied by watering. According to the size of the canopy, apply an appropriate amount of paclobutrazol per plant by watering.

The above is an introduction to flower promotion techniques for sugar oranges. We hope it can help you. To learn more related knowledge, please follow us.