What are the planting time and maturity season of radishes?
Radish is a vegetable with relatively large consumption. For rural families, mutton stewed with radish during the Chinese New Year and the refreshing sweet-and-sour radish in summer are both very delicious. There is also a saying in rural areas, “Eat radish in winter and ginger in summer.” So is radish a vegetable that matures in winter?
Radish Planting Time
Spring radish: sown in early spring, harvested in early summer, with a growing period of generally 25-60 days. It is relatively commonly cultivated in the vast areas north of the Yangtze River in China. In the middle and lower reaches of the Yangtze River, such as Shanghai, Nanjing in Jiangsu Province, and Wuhan in Hubei Province, it is sown in February-March and harvested from April to early June. In the Huang-Huai-Hai region, it is sown in March-April and harvested from early May to June. In high-latitude and high-altitude areas such as Northeast China, Northwest China, and northern North China, it is sown in April-May and harvested in June-July.
Summer radish: sown in May-June and harvested in July-August; if sown too early, it tends to bolt prematurely, and it is mainly grown as a supplement during the autumn slack season.
Autumn radish: in the warm areas of North China and Northwest China, it is sown from late July to early August and harvested from late October to early November; in the colder areas of Northeast China and Northwest China, it is sown in early to mid-July and harvested in early to mid-October; in the cold high-altitude areas of northern China, sowing needs to be advanced to mid-June, with harvest from late September to early October.
Winter radish: the sowing period for winter radish is generally best chosen in early to mid-September. If sown too late, because the temperature is relatively low, the leaf cluster will not grow enough, resulting in low yield.
For off-season radish cultivation, depending on the variety, sowing generally begins in April-May in mid-altitude areas of 800-1200 m, with harvest in June-July, while in high-altitude areas it is sown in May-July and harvested in July-September. Alpine radish cultivation uses varieties with strong winter habit and grows two crops, with marketing possible from June through the end of October.
Radish Maturity Season
Judging by the growing periods of white radish and carrot, they cannot be harvested in all four seasons.
In China, the flowering period of white radish is from April to May each year, and the radish maturity period is from May to June each year.
Carrots are divided into spring and autumn harvests.
Spring carrots are harvested 60-90 days after sowing, that is, from June to August.
Autumn carrots are generally harvested before the soil freezing period, about 100 days after sowing, from August to early October.
Growing Conditions for Radish
1. Temperature: Radish is a semi-cold-tolerant vegetable. The seeds can germinate at 2-3°C, with an optimum temperature of 20-25°C. The seedling stage can tolerate a temperature of 25°C and also a low temperature of minus 3°C. The optimum temperature for stem and leaf growth is 15-20°C, and the optimum temperature for fleshy root growth is 18-20°C.
2. Water: The effective soil water content suitable for fleshy root growth of radish is 65-80%, and the air humidity is 80-90%. High air humidity can improve quality, but soil moisture should not be excessive either; uneven water supply makes the fleshy root prone to splitting.
3. Soil: Radish is not strict about soil requirements, but sandy loam with deep soil layers, loose texture, and good water retention and fertilizer retention performance is best, and the suitable soil pH value is 5.3-7.
4. Nutrition: Among nutrient elements, radish absorbs the most potassium, followed by nitrogen, and then phosphorus. For every 1000 kg of radish produced, it absorbs about 5.55 kg of nitrogen, 2.6 kg of phosphorus, and 6.37 kg of potassium, with a ratio of the three elements of 2.1:1:2.5.
5. Light: Radish growth requires sufficient sunlight. With sufficient sunlight, the plants are robust, photosynthesis is strong, material accumulation is greater, the fleshy root expands quickly, and the yield is high. Plants that have completed vernalization differentiate flower buds and send out flower branches relatively quickly under long-day conditions and higher temperatures.
Harvesting Techniques for Radish
1. Harvesting standards
1. When the leaf color turns lighter and the underground stem has fully expanded, harvest in time;
2. Uniform size is required, with no fibrous roots, no mud, no forked roots, no deformities, no pithiness, no wounds, and no gray heart;
3. Because consumer markets in different regions have different requirements for radish size, the harvesting standards also differ. Some regions want radishes of more than two jin, while some regions want radishes of less than two jin, so the size standard for harvesting should be determined according to market demand.
2. Precooling and transport: Put into a cold storage for precooling (2-4°C) for about 10 hours, then load with insulation for transport to market.
The development of technology has made it possible to grow radishes all year round, and radish cultivation does not necessarily have to rely on greenhouse cultivation techniques. Depending on the different radish varieties, refreshing radishes can be eaten during most of the year, so there is no need to be too fixated on what season radish is a vegetable of.