Forchlorfenuron (CPPU) promotes crop growth by accelerating cell division, differentiation, and enlargement; it facilitates organ formation, fruit set, and fruit expansion, while also enhancing photosynthetic efficiency. 

Specific application methods vary significantly depending on the crop type, growth stage, and treatment technique; it can be applied via spraying, fruit dipping, or direct treatment of fruit stalks and young fruit. Learn more about our Forchlorfenuron (CPPU) products for available formulations and specifications.

This guide summarizes common CPPU application methods and concentrations for different crops.

CPPU for Fruit Setting and Fruit Enlargement

Kiwifruit

Apply 5–20 mg/L CPPU by dipping or evenly spraying the fruit once about 20–25 days after flowering. The treatment can increase individual fruit weight and promote fruit enlargement.

For information on the application of plant growth regulators at various stages of kiwifruit development, please consult the crop solution page.

Loquat

When young fruits reach approximately 1–1.5 cm in diameter, dip the fruits once with a 10–20 mg/L solution. A second treatment can be applied 30–45 days later when necessary to promote fruit development during the later growth stage.

Grape

About 15 days after flowering, when berries reach 10–12 mm in diameter, dip the fruit clusters once in a 5–20 mg/L CPPU solution. This can help increase berry size and soluble solids.

Watermelon

Apply 7.5–10 mg/L CPPU by spraying the young fruit on the day the female flower opens or one day before flowering. The treatment can improve fruit set and help increase sugar content and yield.

Melon

On the day of female flowering or 2–3 days before flowering, apply 10–20 mg/L CPPU by spraying the young fruit or treating the fruit stalk. This can improve fruit set, fruit development, and quality.

Cucumber

When low temperatures, cloudy weather, or insufficient light cause poor pollination, apply 5–20 mg/L CPPU on the day of flowering or one day before. The solution can be applied to the fruit stalk or sprayed on the young fruit.

Sponge Gourd

For varieties such as Qiangfeng, Yucui, and Thai sponge gourd, spraying 10 mg/L CPPU on the ovary on the day of flowering can improve fruit set and increase yield. It may also increase vitamin C and soluble sugar content.

Navel Orange

During the fruit enlargement stage, apply 10–15 mg/L CPPU once to the fruit stalk or the area around the young fruit. This can promote fruit enlargement and increase yield.

Strawberry

Apply 20 mg/L CPPU once by dipping the fruit approximately 6–11 days after flowering to promote fruit enlargement and improve yield.

Waxberry

During the young fruit stage, spray 10 mg/L CPPU once. The treatment can increase individual fruit weight and promote fruit enlargement while improving total sugar and vitamin C content.

Peach

Approximately 30 days after flowering, spray young fruits with 10–20 mg/L CPPU to promote fruit enlargement and increase individual fruit weight.

Plum

Apply 5–10 mg/L CPPU once during flowering or after flowering to improve fruit set.

Shatian Pomelo

About 5 days after full bloom, evenly spray young fruits with 5–10 mg/L CPPU. It can improve fruit set and promote fruit enlargement.

Longan

Spray young fruits with 20 mg/L CPPU approximately 20–30 days after flowering to promote fruit enlargement and improve yield.

Mango

Start treatment 7–10 days after flowering, when young fruits are approximately the size of a peanut.

For whole-plant spraying, a concentration of 1–3 mg/L can be used. Alternatively, young fruits can be sprayed with 10–20 mg/L CPPU.

Applications can be repeated 3–4 times during the growing season, with an interval of at least 10 days. CPPU should not be used within one month before harvest.

Excessive concentrations may reduce the sugar-to-acid ratio and affect fruit quality. In some production programs, CPPU is used together with approximately 50 mg/L gibberellic acid (GA3).

Cherry

Approximately 15 days after flowering, evenly spray the plants with 5 mg/L CPPU. The treatment can increase fruit size and individual fruit weight and may also promote fruit coloring.

Taiwan Green Jujube

During the flowering period, spray flower clusters with 5 mg/L CPPU. It can promote fruit enlargement and may also increase leaf thickness and greenness.

Citrus

Apply 5 mg/L CPPU at 3–7 days and again at 25–35 days after flowering. In some production programs, CPPU is combined with 25–50 mg/L gibberellic acid (GA3) and applied directly to the fruit. This treatment is used to improve fruit set and reduce physiological fruit drop.

CPPU for Grain and Field Crops

CPPU is not limited to fruit crops. It can also be used in some field crops to support grain development and yield.

Rice

During the heading stage, spray with 5–10 mg/L CPPU. The treatment may improve milled rice yield, increase 1,000-grain weight, and support overall yield.

Wheat and Barley

During the booting stage, foliar spray of 5–10 mg/L CPPU. It can promote grain filling and help increase yield.

Soybean and Common Bean

Apply CPPU 1-5mg/L from the beginning to the peak flowering stage. A low-concentration foliar spray can help reduce poorly developed pods and promote grain filling.

Peanut

From the pegging stage to pod development, apply 1–5 mg/L CPPU as a foliar spray. The treatment can improve the proportion of well-developed pods and increase yield.

Radish

When fleshy roots begin to enlarge, spray the whole plant with 4 mg/L CPPU. Four applications can be made at approximately 10-day intervals. This treatment is used to reduce premature bolting and hollow root formation while supporting root development.

CPPU for Post-Harvest Preservation

In addition to fruit enlargement and yield improvement, CPPU has also been studied and used in some post-harvest applications.

Leafy Vegetables

Spraying leafy vegetables with 1–2 mg/L CPPU before harvest can help slow chlorophyll degradation and extend the fresh-keeping period after harvest.

Lychee

During the young fruit stage, treat green or slightly red lychee fruits measuring approximately 25–30 mm in diameter with 5–10 mg/L CPPU.

The treatment may delay harvest maturity by approximately 14–21 days. It can also help maintain fruit color, reduce browning, and slow deterioration during storage.

Mango

Dip harvested mangoes in a 25 mg/L CPPU solution for approximately 5 minutes. When stored at around 25°C, the treatment can help delay post-harvest aging and deterioration.

CPPU Application Tips

The appropriate CPPU concentration depends strongly on the crop and application stage. Higher concentrations do not necessarily produce better results and may negatively affect fruit shape, sugar-acid balance, or other quality characteristics.

For fruit crops, the timing of application is particularly important. CPPU is commonly applied around flowering, fruit set, or the early fruit enlargement stage. Spraying, fruit dipping, and fruit-stalk treatment may require different concentrations.

Before commercial application, always follow the registered product label and local agricultural regulations. The concentrations and application methods in this guide are general technical references and should be adjusted according to the specific product formulation and local use requirements.

For more information about Forchlorfenuron (CPPU), including available formulations and product specifications, please visit our product page.