Yangmei Growing Information

Yangmei is native to mountainous areas with temperate and subtropical climates in China. Its geographical range is similar to citrus and loquat, except that Yangmei's cold resistance is better. 

Currently there are over 400 Yangmei germplasm resources preserved across China with over 300 cultivated varieties. Some of the commonly grown varieties are listed here.

It is difficult to find Yangmei (i.e. Myrica rubra) for use as rootstock in the United States. Fortunately, several related species can be used and are more readily available:

• Myrica californica (Pacific Wax Myrtle) - This plant is native to the Pacific Coast of the United States and has been used successfully as rootstock for Myrica Rubra. Some growers have reported issues with Myrica californica surviving the hot CA Central Valley summers, and that pensylvanica and cerifera have better hot weather survival.  Other growers have expressed concern that trees on myrica californica rootstock may die suddenly, similar to trees on native myrica rubra rootstock; they suggested that one of the other rootstocks might be preferable. 
• Myrica cerifera (Southern Wax Myrtle) - This plant is native to the southeastern United States and has also been used successfully as rootstock for Myrica Rubra.
• Myrica pensylvanica (Nothern Bayberry) - This plant is native to the northeastern United States coastal areas. It has been successfully used as rootstock for Myrica Rubra. There are reports that it may be somewhat dwarfing as compared to other rootstocks.  It is also reported to send out a lot of suckers from the root area.

The roots of Yangmei are symbiotic with actinomycetes (Frankia), forming large and small nodules called actinorhizal, which have function of fixing nitrogen. Actinorhizal are nodular protrusions, grayish yellow, and irregular in size and distribution. 

Note: Members of the genus Frankia are characterized by the ability to form nitrogen-fixing nodules on the roots of certain woody angiosperms. Both the nodules induced by Frankia and the species of plants that bear these nodules are termed “actinorhizal.” The ability of Frankia to induce root nodules, which may provide part of the nitrogen requirements of the actinorhizal host plant, is of considerable importance to forestry, land reclamation, natural ecosystems, and plant genetic engineering. In many field situations, low levels of combined nitrogen in the soil may be limiting to plant growth; thus, the presence of root nodules, which chemically reduce (fix) atmospheric (molecular) nitrogen, overcomes deficiencies of ammonium and nitrate in the soil and aids plant growth.

The root system of economically cultivated Yangmei tress is relatively shallow, and the taproot is generally small. Two thirds of the roots are vertically distributed in the 0-24 inch layer of the topsoil and its horizontal distribution is 1-2 times the diameter of the crown.  

Yangmei experiences three main root growth phases annually:

• First root growth peak: March to April, coinciding with spring shoot emergence.
• Second root growth peak: June to July, during fruit expansion and early shoot maturation.
• Third root growth phase: August to October, supporting new shoot development for the next season

Note: Yangmei is less drought tolerant than species with deeper roots, such as loquats and figs. As a result, it requires more frequent watering. However Yangmei is also susceptible to root rot and care must be taken to avoid water logging the roots. Applying planting techniques similar to those used for avocados, by placing the trees on raised mounds or applying other techniques to ensure soil drainage may improve long term success. Additionally, raised mounds will likely make it easier to provide a soil pH that mimics the native soil conditions in China (4.5 to 6).

There are four types of branch growth of Yangmei based on the different growth periods: namely spring branch from April to May, summer branch from June to July, autumn branch from August to September, and late autumn branch from October to November. 

Most of the fruiting mother branches of Yangmei are formed by spring branch or summer branch. The fruiting branches can be divided into leggy fruiting branches (>30cm), long fruiting branches (20-30 cm), medium fruiting branches (10-20 cm) and short fruiting branches (<10cm). Most of the fruiting branches are mainly medium fruiting branches and short fruiting branches. 

When the proportion of fruiting branches of each Yangmei tree is about 40% the yield is stable. When it exceeds 60%, the tree will tend to bear fruit in alternate years. The fruiting rate of the inflorescence of each fruiting branch is the highest in the top 1-5 nodes, and the first node is 20%-50%. It is suitable to cultivate 30-40% of medium fruiting branches that both bears fruit and grows long shoots, while maintaining the short fruit branches as the mother branches for fruiting. This will maintain stability of the yield. 

Yangmei is a dioecious fruit tree, but there are also a few male flowers that bloom at the base of the female inflorescence, a phenomenon called monoeciousness (hermaphrodite). However, when building a Yangmei production area, 1% to 2% of trees planted should be male to ensure high quality and stable production. 

Male Yangmei is divided into three types according to the color of the flower: rose red, red-yellow, and earthy yellow, among which the rose red type has the highest pollination and fertilization rate. 

Yangmei is a wind pollinated flower with a transmission distance of 2 to 3 miles. The male flower flowering period is 20 to 30 days. The female flower has 7 to 10 flowers per inflorescence and the flowering period is about 15 days. A common pollination technique is to add 1-2% rose red male Yangmei plants  to the orchard by grafting them into high positions or planting male seedlings when establishing an orchard.

Yangmei buds undergo physiological and biochemical changes and morphologic differentiation. From July to August of each year is the time period for distinguishing the leaf buds and flower buds on Yangmei. During this period it is necessary to focus on post harvest cultivation and management of Yangmei to promote good differentiation of flowers for high quality fruit during the next year. In August, the inflorescence differentiates normally, and the stamens appear respectively from September to November. From December to February of the following year the tree is dormant and differentiation continues in March to April of the following year.

The growth and development period of Yangmei is divided into 5 periods, namely: 

Flowering and pollination period: mid-March to early April (lasting about 15 days)

Young fruit formation period: mid-to-late April, that is more than 20 days after ovule pollination, the young fruit swells rapidly, and the green particles form a sphere

Kernel formation period: early May to mid-May (lasting about 14 days), the fruit has been formed, and the fruit diameter increases a little.  The seed shell is fleshy, soft, and light in color.

Fruit hard core period: mid-to-late May (lasting about 10 days), the fruit changes color, the seed kernel develops gradually and fills up, the fruit diameter presents an S-shaped growth curve, the larger the fruit diameter, the faster the kernel hardens. 

Color change and maturity period: early-to-mid June (lasting about 10 days), the fruit changes color, the fruit grows very fast, which is the second peak of development. The fruit diameter reaches 2.1-3.9 cm. It only takes 7-8 days for the fruit surface color to change from light yellow to red, and only 3-4 days for red to change to dark purple and for the accumulation of sugar in juice. The sugar content of the fruit is positively correlated with the degree of coloration. That is, the darker the coloration, the higher the sugar content. It is mainly composed of glucose and fructose, and the sugar content increases significantly 14-21 days before full maturity. Regardless of wheter the fruit is dark purple or light yellow fruit, the sugar content of large fruit is higher than that of small fruit. The smaller the fruit size and the lower the maturity of the fruit, the higher the acidity. 

Yangmei is a warm-loving, shade tolerant, evergreen tree species, with an optimum annual average temperature of 59-70 deg F, able to survive a lowest extreme temperature of 8-16 deg F. Relative humidity in its natural climate is fairly high at more than 80%. The flower is resistant to temperatures down to 32-36 deg F. The high temperature tolerance of the fruit during the development and maturity period is 86-97 deg F, and the high temperature tolerance of the branches during the flower bud differentiation period is 84 deg F. 

Note: Yangmei has been successfully grown in California’s Central Valley in temperatures above this range in the summer (100-110 deg F).

Yangmei likes sandy red soil or yellow soil rich in gravel, and the most suitable soil pH is 4.5-6.0.  Artificial cultivation of Yangmei in China is typically conducted at altitudes of less than 2500 feet with 300-1300 feet being most suitable. 

Yangmei cultivation has significant economic benefits and long economic life. Its roots are symbiotic with actinomycetes (a soil bacteria), it can grow in barren mountainous areas, and has low production costs. Yangmei fruits are bright in color, sweet and sour, unique in flavor, and rich in nutrients. They have a dense canopy and are evergreen all year round. 

In the main producing areas of China, if grafted seedlings are cultivated properly, they can generally bear fruit in 3 to 6 years, and enter the peak fruit bearing period after 8-10 years. 

Yangmei has a wide range of uses. With its beautiful tree shape and dark green leaves, the 15 year old robust Yangmei tree is an ornamental gardening tree. Yangmei’s fresh branches and leaves are not easy to burn and can be planted as a forest firebreak to prevent forest fires. In addition to being eaten fresh, Yangmei fruits can also be processed into canned Yangmei in syrup, jam, candied fruit, juice, dried fruit, fruit wine and other foods.

Yangmei is an evergreen small tree with strong vigor, well developed root system, wide adaptability, and easy cultivation. Yangmei trees like shade and are non-leguminous woody nitrogen-fixing plants. In slightly acidic mountain soils, their roots form nodules in symbiosis with actinomycetes, which have a persistent symbiotic nitrogen-fixing ability. They are drought-resistant and are able to grown in barren landscapes.  Yangmei trees are more shade-tolerant than other green fruit trees, making them well-suited for north-facing slopes or areas with large tree canopies.

Yangmei can be planted alone or mixed with other fruit trees. People have long planted Yangmei with pine and cypress for greening and reforestation. Japan has published the results of a mixed planning experiment, where Yangmei was planted with red pine or black pine, and the results showed that it could promote the growth of red and black pine. 

Yangmei varieties can be grouped into three types according to fruit maturity: early-maturing varieties, mid-maturing varieties, and late-maturing varieties.

See the chart on this page for ripening dates. (approximate)

Yangmei can also be propagated using air layering and cuttings. However, the root systems of air layered and cutting-propagated seedlings are far less developed than those of grafted seedlings. These seedlings also lack overall vigor compared to grafted ones, making them less commonly used in commercial production.

The propagation success rate and survival rate of Yangmei through air layering are relatively low, so it is rarely used in commercial production. 

In cases where layering is done in November, the healing of the wound tissue is relatively slow. For layering done between March and June, roots generally begin to emerge around September to early October when temperatures drop. For layering performed in October, rooting may not occur until May of the following year. Thus, June is the optimal time for air-layering, as it results in the shortest root development period.

Use one-year-old branches that are located on the outer part of the tree canopy, preferably from the current year’s summer or autumn growth (semi-lignified wood). Remove the underdeveloped tip of the cutting. Cut just below the first node using a sharp knife. Each cutting should have 3–5 leaves and be 5-6 inches in length. Cuttings should have one stem. 

Spring cuttings should be taken in mid-April. Summer cuttings should be taken in early July.

Cutting temperature and humidity control is mainly achieved through adjusting the plastic film and watering. From mid-April to late June, temperatures inside the rooting tunnel should be kept at 77-82°F. Humidity should be 90–95% for the first two months, then gradually reduced to 85%.

Experimental results indicate that under yellow shade film, cuttings treated with 200 mg/L naphthaleneacetic acid (NAA) (Note: roughly 0.8 g/L IBA) had a rooting rate of 51.5%, while those treated with 50 mg/L NAA (Note: roughly 0.2 g/L IBA) had a rooting rate of 22.7%. Cuttings under clear plastic (control) had a rooting rate of 4.8%.

Under white shade film, cuttings treated with 200 mg/L NAA had a rooting rate of 12.1%, those treated with 50 mg/L NAA had a rooting rate of 6.1%, and those under clear plastic (control) had a rooting rate of only 3.5%.

These results suggest that yellow shade film promotes the rooting of Yangmei cuttings.

Note: Yellow light may enhance auxin activity, promoting stronger root initiation, and some studies suggest that white light may inhibit auxin accumulation. The proposed technique uses film to alter growing conditions (temperature and humidity). The results of yellow film are likely the result of a balance of temperature, humidity, and auxin activity factors. Assuming temperature and humidity are otherwise controlled, there may still be a benefit to controlling the light wavelength with red spectrum light being more beneficial for root propagation than blue spectrum light. 

Soil pH directly affects the availability of various nutrients essential for Yangmei growth, particularly the availability of phosphorus, trace elements, and other key nutrients. If the pH is too high or too low, it can lead to nutrient deficiencies.

In southern growing regions in China, soils tend to be more acidic, which can negatively affect Yangmei growth if pH is too low. In alkaline regions, soil is often calcareous and pH is too high, making it unsuitable for Yangmei cultivation. The native soil in Yangmei growing regions in China is typically between a pH of 4-6. The most suitable soil pH for Yangmei is 4.5 to 6. The region when Dongkui is grown is typically 5.5 to 6.0, while other regions are more typically 5.0-5.5.

Excessively acidic soils (low pH, pH<4.0) can increase aluminum and iron solubility, which can be toxic to root systems. It can reduce the availability of essential nutrients like phosphorus, magnesium, and calcium, lead to weaker root development and increased disease susceptibility, and cause soil structure degradation, making it prone to compaction and waterlogging. Acidic conditions can also alter microbial populations, increasing the likelihood of root diseases. Some Chinese reports list a pH of <3.5 as Very Low for Yangmei.

Excessively alkaline soils (pH >8.0) can reduce the solubility and absorption efficiency of iron, zinc, manganese, and boron, leading to nutrient deficiencies. It can cause physiological disorders, affecting Yangmei fruit quality, promote soil hardening and reduce organic matter decomposition, further impacting soil fertility. Excessive nitrogen fertilizer use in alkaline soils can cause imbalanced microbial activity, leading to reduced nitrogen-fixing capacity. Some Chinese reports list a pH of >6.5 as Very High for Yangmei. 

Yangmei has a strong nitrogen-fixing capability, enabling it to absorb nitrogen from the atmosphere through symbiotic associations. Under normal conditions, Yangmei can meet most of its nitrogen needs through soil reserves. Generally, 20%–25% of total nitrogen should come from fertilization to promote healthy tree growth. However, excessive nitrogen application can lead to excessive vegetative growth, reducing flowering and fruiting potential. A balanced nitrogen supply is essential to maintain stable yields.

In addition to nitrogen, phosphorus and potassium fertilizers play an essential role in nutrient absorption and root development. Yangmei benefits from organic phosphorus decomposition, which increases nutrient availability. Mycorrhizal fungi enhance root surface area, further improving phosphorus uptake efficiency.

Research has shown that Yangmei requires nitrogen and phosphorus in specific ratios, depending on tree growth stages and soil conditions. Young trees require a ratio of N-P-K = 2:1:2 to promote balanced vegetative growth. During fruiting stages, a ratio of N-P-K = 2:1:5 is optimal. Since fertilization needs vary by region, applications should be adjusted according to soil nutrient levels, local climate, and orchard conditions.

To ensure optimal nutrient uptake, nitrogen, phosphorus, and potassium applications should be balanced and strategically timed.

During key growth stages, foliar application of micronutrients can improve fruit quality and yield. Research indicates that foliar spraying of phosphorus and potassium enhances fruit coloration and sugar content. A single foliar spray can be applied during early fruit expansion or near harvest to maximize fruit quality.

Among micronutrients, Yangmei is particularly sensitive to boron deficiency. Other elements, such as calcium, iron, and zinc, also play important roles in fruit set and quality. However, boron application has a more significant effect on fruit setting rate and fruit quality improvement.

Symptoms of boron deficiency in Yangmei include: poor flower bud differentiation, reduced fruit set, leaf distortion, yellowing of young leaves, and irregular fruit development. Corrective Measures are to apply 0.1%–0.2% boron fertilizer if early symptoms appear. If fruit remains small or develops cracks, apply foliar boron spray to enhance absorption. Severe boron deficiency manifests as leaf curling, weak shoot growth, and brittle branches. In this case, root fertilization should be used.

Fertilization for young Yangmei trees focuses on promoting growth and early canopy formation. Besides weed control, fertilization is essential to stimulate root development and accelerate canopy expansion. 

During early spring (March to July), multiple applications of nitrogen, phosphorus, and potassium fertilizers should be made to support root and shoot growth. The ideal NPK ratio is 2:1:2 to ensure balanced nutrient uptake.

Once the tree enters the fruiting phase, the canopy stabilizes, and the focus shifts to supporting fruit development. At this stage, Yangmei’s fertilization needs are determined by its fruiting characteristics and growth cycle. Branch distribution, shoot growth, and fruit set patterns influence nutrient requirements. Key nutrients such as boron, calcium, and potassium should be supplemented during flowering and fruit expansion.

Fertilization should align with key growth phases, ensuring that nutrients are available when trees need them most. For fruit-bearing trees, the recommended N:P:K ratio is 4:1:5. The exact ratio can be adjusted based on soil conditions.

Note: this N-P-K ratio for fruiting is slightly different than the value reported earlier which was approximately 2:1:5

Yangmei trees typically require three fertilization cycles per year:

Pre-flowering fertilization ("Flower Bud Fertilization"). This is applied in February, before spring flowering begins. This is the most important fertilization period, as it significantly impacts fruit set and early growth. If organic fertilizer is used, it should be applied early to allow nutrients to become available over time.

Fruit Expansion Fertilization ("Fruit Swelling Fertilization"). This is applied in May to June, to support rapid fruit expansion and seed development. This stage determines fruit size and overall quality.

Post-Harvest Fertilization ("Recovery Fertilization"). This is applied in July, right after fruit harvest. This replenishes nutrients that were depleted during fruiting. For older trees, post-harvest fertilization is particularly important to sustain high yields over multiple years.

If trees have produced a heavy fruit load, additional fertilizers should be applied to promote strong growth for the following year.

When fruit diameter reaches 0.5 cm, manual thinning should begin. Remove excess or poorly developed fruit before the hardening period to concentrate nutrients on high-quality fruit.