1. When Loquat Trees Flower and When the Fruit Ripens
The loquat is an evergreen tree originally from central and southern China. In Japan, it flowers from early November to late February. [1] The fruit then ripens in May or June, turning a yellowish-orange color. [1]
If you count the days, the flowering period lasts about 4 months. This means that throughout the entire winter season, flowers are blooming somewhere on the branches. [1]
Between the winter flowering and the early summer harvest, the coldest part of the year occurs. Interestingly, the sources reviewed do not explain why loquats flower in winter. The known fact is simply that after flowering, they spend the winter as fruit. [1] So, are these tiny new fruits safe from the cold?
2. Why the Young Fruit's Embryo Freezes in Winter
According to research from Chiba Prefecture, loquats set fruit in early winter. The young fruit is very sensitive to cold. It must survive the coldest period of the year. [2]
If the young fruit is exposed to low temperatures, the embryo inside can freeze and die. This is called "cold damage." When this happens, the fruit stops growing. [2] The embryo is the part that will eventually become the seed.
For the variety 大房, researchers estimate that economic damage begins when the rate of cold damage exceeds 20%. This happens at approximately -4.02 degrees Celsius. [2] This does not mean all fruit will die if the temperature drops below -4 degrees. It is a guideline for when damage becomes significant. This number can change depending on the variety and location. [2]
Another guide notes that the tree itself may die if temperatures drop below -3 degrees Celsius. It suggests that sloped land with good drainage is better because cold air does not pool there. [3] Note that the -4 degree figure for fruit and the -3 degree figure for the tree measure different things, so they should not be compared directly.
3. How Farmers Thin the Fruit Clusters and Cover the Fruit with Bags
Farmers begin their work before the flowers fully bloom, in October or November. They perform a task called "thinning clusters" to reduce the number of fruit-bearing clusters. [3] Later, they thin the fruit further, leaving only 3 to 4 fruits per cluster before putting on bags. [3] This number is just an example and varies by method.
From March to early April, farmers wrap each remaining fruit in a bag. Pests begin to appear during this time, so it is best to apply the bags as early as possible. [3]
The bags protect the fruit from pests like weevils and from damage or spots caused by strong sunlight. [3][4] The sources state they protect against insects and sunlight. They do not say that the bags protect the fruit from winter cold itself. [3]
4. The Large Seeds Inside a Loquat
When you cut open a loquat, the inside is divided into two chambers. Each chamber contains 1 to 2 large seeds. [1] The edible part is the flesh surrounding these seeds.
Because the seeds are so large, the amount of edible flesh is reduced for a fruit of the same size. Many people are surprised by the size of the seed when they eat a loquat. [1]
People did not just throw these large seeds away. Seeds were planted and new varieties were developed. [1]
5. How Seeds from Chinese Trade Ships Led to New Loquat Varieties
Current cultivated varieties are said to come from seeds brought to Nagasaki from China on trade ships around 1830 to 1848. [1] The variety "Mogi" also came from China to Nagasaki in the late Edo period. [6]
While loquats have been known in Japan for much longer, this story focuses on the history of the varieties grown today. [1]
In 1879, Yoshio Tanaka brought seeds from Nagasaki to Tokyo and grew them. The variety born from these seeds is called "Tanaka." [6]
According to a page from Funabashi City, the average weight of a "Tanaka" fruit is about 60 grams, while "Mogi" is about 40 grams. [6] This means Tanaka is about 1.5 times heavier than Mogi on average. These are average guidelines from the data, not a comparison of single fruits. [6]
6. How Chiba Prefecture Took 15 Years to Develop the Seedless Loquat 'Kibo'
"Kibo" is a variety developed by Chiba Prefecture. It is described as the world’s first seedless loquat. [5] Using a technique involving triploidy, breeding began in 1991 and the variety was registered in 2006. [5] This took 15 years from start to registration.
Because it has no seeds, the proportion of flesh is higher than in regular loquats. [4] This refers to the percentage of flesh, not the total weight of one fruit. [4]
The average fruit weight is 70 grams, with a sugar content of 11.5 and acidity of 0.2. Harvesting starts in late May. [5] Compared to the 60 grams of "Tanaka," Kibo is slightly heavier on average. [5] It is considered suitable for greenhouse cultivation, which allows for stable production. [5]
7. How to Spot Loquat Trees in Winter
Loquats are evergreen trees, so they keep their leaves all year and are easy to find in winter. If you see a loquat tree in your neighborhood between November and February, look at the tips of the branches. You might see flowers or tiny fruits. [1] Please only look from public areas like the street, and do not enter private yards.
In spring, you might see bags on the fruit. As noted earlier, these bags protect against insects and sunlight. [3]
If you have the chance to eat a loquat, try counting the seeds and the chambers inside. The sources say there are 2 chambers with 1 to 2 seeds each. Do you find the same when you cut one open? [1]
If you want to read more, the Chiba Prefecture research page covers cold damage temperatures, and the Chiba Prefecture variety page covers the development of Kibo. [2][5] Why do loquats flower in winter? Searching for that answer might be your next question.