When is the best time to plant spinach?

Although spinach has strong adaptability, its growth is often inhibited under high temperature conditions. In addition, high temperatures can also reduce the germination rate of spinach seeds , which may result in uneven emergence of seedlings. So when is the best time to plant spinach?

When is the best time to plant spinach?

Spring sowing: Spring sowing is usually carried out after the last frost. The best sowing time in North and Central China is February-March, and the harvest period is April-May.

Autumn sowing: Autumn is the main sowing season for spinach, especially before the temperature starts to drop. The best sowing time in North China and Central China is from late August to early October, and the harvest period is from October to April of the following year.

Southern Region: In the warm south, the sowing period can last from August to May of the following year.

Cold northern regions: In these areas, sowing time should be advanced appropriately to ensure that spinach has adequate growth time before the onset of winter cold.

Spinach seeds germinate best at a temperature of 20-22°C, the suitable temperature for seedling growth is 22-25°C, the suitable temperature for rosette growth is 17-22°C, and the optimum temperature for head formation is 12-18°C. Therefore, when the daytime temperature drops to 20-25℃ in autumn, it is the best time to sow spinach.

Spinach Planting Tips

1. Soil preparation and fertilization, using high-bed planting method

Spinach is mostly sown by direct seeding. Choose a plot with good drainage, deep soil, sufficient fertility and loose soil for deep plowing. Apply 3,000 kg of fully decomposed farmyard manure per mu as base fertilizer. For soils with better fertility, the application amount can be appropriately reduced, otherwise it should be increased. The method of applying base fertilizer is to spread it all over before plowing the land , turn two-thirds of the fertilizer into the soil, and apply the remaining one-third on the soil surface after plowing the land and mix it with the surface soil. This method of fertilization can meet the nutritional needs of spinach throughout the early and late growth stages. In the rainy southern regions, high ridges should be used for planting to facilitate drainage, and the ridge width should be controlled at 1 to 3 meters.

2. Seed selection

When selecting seeds, you should give priority to large, plump, and high-specific-grain seeds to ensure rapid growth and high yield of spinach. It is advisable to use fresh seeds sown in the autumn of the previous year and harvested this year. Spinach is divided into two types: pointed leaves and round leaves. The pointed leaf varieties have thorns on the surface of the seeds, while the round leaf varieties do not. For overwintering spinach, you should choose cold-resistant pointed-leaf varieties; summer spinach is prone to bolting due to high temperatures and long days during its growing period, so you should choose heat- and drought-resistant round-leaf varieties.

3. Seed treatment

The seeds of pointed-leaf varieties often stick together because they have thorns on the surface, affecting the quality of sowing. Because the peel of spinach seeds is hard and thick and has poor water absorption, germination is slow. Before sowing, you need to gently tap the seeds with a wooden stick to break the exocarp and remove the thorns. Then soak the seeds in cold water for 12 to 24 hours, wrap them with a wet cloth, and germinate them at room temperature. After the seeds turn white (about 3 to 5 days), they can be sown. Spinach sown in summer should be germinated at 15 to 20℃.

4. Sowing method

Spinach is usually sown by direct seeding, which involves spreading the seeds evenly on a flat surface. The row spacing for row sowing should be 10 to 15 cm, and the row spacing for hole sowing should be about 16 cm. After sowing, cover with a layer of fine soil about 1 cm thick and water thoroughly. The sowing rate per acre is about 5 to 6 kilograms.

5. Field management

Keep the soil moist before germination to promote emergence of seedlings. When the seedlings grow two true leaves, the growth rate accelerates. At this time, watering and topdressing should be done in time. Nitrogen fertilizer should be applied as the focus during the growth period, and generally 2 to 3 times of topdressing is required. For weaker seedlings, apply quick-acting fertilizer with high nitrogen content along with water, at a rate of about 10 kg per mu, to promote their growth. Attention should also be paid to thinning and weeding during the seedling stage. When winter comes, spinach leaves stop growing and having 4 to 6 leaves is enough to safely survive the winter. During the winter, pay attention to timely watering, cold protection and snow removal. After wintering, it takes 30 to 40 days for the plants to resume growth before harvest. During this period, timely top dressing and watering are required, and disease and pest control should be strengthened. Spinach sown early can be harvested in about 60 days, while spinach sown late will take 80 to 90 days to be available. Therefore, topdressing should be applied early for early sowing, and can be appropriately delayed for late sowing. For overwintering spinach, control watering before winter, and water and fertilize in time after two true leaves grow.

6. Harvest

Spinach plants are ready to harvest when they are 15 to 18 cm tall and their leaves are fully grown. 6 to 8 days before harvest, you can use 1 gram of "920" hormone added to 40 to 100 kilograms of water to spray the plants to increase yield. Harvesting should be carried out in batches. Some large seedlings should be picked first, and the remaining weak seedlings should continue to be fertilized and harvested after they grow up.

In general, spinach is a vegetable that prefers warm and cool climates. Its planting time varies depending on the region and climatic conditions, but spring and autumn are generally the best seasons.