Agrotechnology for cultivating broccoli and Chinese cabbage in greenhouses and open soil

Broccoli is cultivated as an annual or biennial crop. This cold-hardy plant tolerates frost down to -10 °C, but requires moderate warmth between 16–25 °C for optimal development. To obtain a high-quality harvest on schedule, an agronomist must correctly calculate the sowing time and the plant nutrition plan.

• Optimal growing temperature — 16–25 °C
• Cold resistance — down to -10 °C
• Transplant age for planting — 35–45 days
• Soil moisture depth — up to 40 cm

The foundation for planting is soil that has been deeply ploughed and, if necessary, limed in the autumn. The fertilizer application system for broccoli depends on the season and the region of cultivation. Nutrient application can be planned according to the following schedule:

Broccoli seed can be sown directly into open soil in early May, in which case the harvest will mature by mid-July. However, to guarantee a uniform harvest, it is better to cultivate the crop using transplants. Sowing in boxes or cold hotbeds is conducted in stages, at intervals of 10–20 days.

In trials for the conditions of the Non-Chernozem region, sowing in greenhouses began in mid-March for transplanting at the end of April. For later planting dates, seed was sown in hotbeds until the end of May to move the plants to the field at the end of June. In the greenhouse, the temperature regime is strictly maintained: 15–18 °C during daylight hours and 10–12 °C at night.

Broccoli emergence occurs on the 3rd–4th day after sowing. After 10–15 days, the seedlings form 3–4 true leaves. Transplants aged 35–45 days, having 5–6 true leaves at the time of planting, are considered the most viable.

The planting pattern in the field is chosen based on the intended harvesting technology. To obtain only large central heads, the transplants are planted more densely — 50 (60) × 20 (30) cm. If harvesting side shoots is planned, the plants are given more growing space according to a 60 × 40 (45) cm pattern.

Care for the plantings includes standard agrotechnical measures: weeding, loosening of row spacing, hilling, and irrigation. During irrigation, it is important to moisten the soil to the depth of the root system — up to 40 cm. For additional plant stimulation before the heads set, a liquid top dressing of cow manure (diluted 1:10) or a solution of mineral fertilizers at a rate of 30–40 g per 10 liters of water is applied.

Cut broccoli heads are sold or processed immediately. To extend the shelf life of the product's marketability, harvesting is planned for early morning or late evening.

Peking cabbage

Peking cabbage is one of the fastest-maturing crops in the vegetable crop rotation. From the moment of emergence to the harvesting of the leaf rosette or loose head, only 18–40 days pass. The seed is capable of germinating at low air temperatures, and the crop itself performs best on loose and fertile soils.

• Growing season — 18–40 days
• Optimal germination temperature — 16–20 °C
• Seed application rate — 1–2 g/m²
• Transplant age for half-head — 20–25 days

This crop is grown both independently and as a filler crop in greenhouses when planting cucumbers or tomatoes. Soil preparation for Peking cabbage is carried out with the mandatory application of organic matter and a mineral complex. The nutrition and top dressing schedule is presented in the table:

For direct sowing, 1–2 g of seed is used per 1 m². For accelerated production of half-heads, the crop is planted as 20–25-day-old transplants using a 20 × 20 cm pattern. When growing cabbage as a filler crop, the temperature regime is adjusted to the requirements of the main crop.

In monoculture, it is important to strictly monitor the temperature at different stages of seedling growth:

1. Until seedling emergence, maintain the temperature between 20–22 °C.
2. Immediately after seedling emergence, lower the temperature to 10–12 °C for 5–6 days to prevent etiolation.
3. During the active growing season, maintain 18–22 °C during the day and 14–16 °C at night.