Edible Mushroom Cultivation Methods and Spring Broccoli Planting Techniques
Spring broccoli planting techniques are as follows:
1. Variety selection: high-quality early-maturing varieties.
2. Seedling stage management: Spring-planted broccoli is generally raised as seedlings in February-March. As spring temperatures are low, transplanting can be done after one month.
Broccoli seedling raising generally has two methods: one is direct sowing on the ground to raise seedlings, and the other is plug tray seedling raising. For plug tray seedling raising, a 128-cell standard seedling tray can be used, sowing 1 seed per cell, and after sowing, covering with 0.5 cm of substrate material. Regardless of which seedling raising method is used, because broccoli has relatively high water requirements during the seedling stage, care should be taken to keep the soil moist; during the emergence stage, the relative soil humidity should be about 70%-80%. It must not be too dry or too wet, which would affect the growth of the seedlings. In addition, because the outside temperature is relatively low during the seedling stage, attention should be paid to covering with film for insulation, and at night, straw curtains should be added for insulation.
3. Cultivating strong plants:
Timely planting: For open-field spring cultivation, this is generally in mid-to-late March, and when the seedlings grow to 5-6 leaves, it is the suitable period for planting. If planted too early, the seedlings may encounter low temperatures and form heads prematurely; if planted too late, the seedlings age, which affects the growth and development of the seedlings after planting and makes the flower heads smaller. Therefore, planting must be done at the appropriate time.
Planting density: Generally speaking, a plant spacing of 50-60 cm is sufficient for broccoli. If planted too sparsely, there is no yield; if planted too densely, both yield and quality cannot be guaranteed. Because broccoli has many leaves, a single broccoli plant has as many as 17 leaves just in leaves, and they spread out widely. If planted too densely, the leaves cannot extend to both sides, become upright, and the flower head does not develop well.
Cover with small arched sheds to raise temperature and promote seedling recovery: After broccoli is planted, because the outside temperature is relatively low and broccoli is not tolerant of frost, insulation work should be done after planting to promote seedling recovery. For open-air cultivation, when planting in mid-to-late March, because the outside temperature is relatively low, it is best to temporarily cover with small sheds for insulation. Generally, the shed should be kept closed for 4-5 days. After that, as new leaves unfold and the outside temperature rises, ventilation should be gradually increased so that the temperature inside the small arched shed is not higher than 25°C. Generally speaking, when the outside temperature is above 15°C, that is, around April 20 each year, the small arched frames need to be removed to avoid excessive temperature affecting flower bud development.
Timely watering and fertilizing: After the plants recover from transplanting, they quickly enter a period of rapid growth. To ensure the supply of fertilizer and water needed for plant growth, watering and fertilizing should generally be done in a timely manner after seedling recovery, so that the plants quickly reach a certain number of leaves, which is conducive to the production and accumulation of nutrients. Generally, after seedling recovery, one timely watering should be given, and afterward care should be taken to keep the soil moist to prevent water shortage before and after flower bud differentiation (6-7 leaves), which would cause premature budding. About 10-15 days after planting and seedling recovery, apply 10 kg of urea and 15-20 kg of compound fertilizer per mu with irrigation to promote plant growth and cultivate strong plants.
4. Grasp the key management points to prevent abnormal flower heads
Skillfully apply fertilizer and water to promote flower head expansion: During cultivation, at the budding stage and before the flower head expansion stage, topdressing should be done in a timely manner. Per mu, 10 kg of urea, 15-20 kg of diammonium phosphate, and 5 kg of potassium fertilizer can be applied. However, excessive application of nitrogen fertilizer should be avoided. When there is too much nitrogen fertilizer, the flower branches grow rapidly and after elongating are likely to cause loose flower heads. After broccoli enters the flower head expansion stage, watering must not be blind. Especially when broccoli is almost fully grown, it is best not to water, to prevent loose heads and affect marketability. If the soil is very dry, a small amount of water can be applied appropriately.
Regulate temperature and light to prevent flower heads from turning yellow and bud scorching: When broccoli enters the flower head expansion stage, insufficient sunlight or strong light can cause the flower heads to turn yellow or the buds to scorch. To avoid this situation, when dense planting causes the outer leaves to be too luxuriant, the flower heads turn yellow because they cannot get sufficient light, so leaves should be appropriately removed. Under too strong light, leaves can be picked and placed over the flower heads to reduce the occurrence of scorched buds and flower heads. While regulating light, attention should also be paid to temperature control. During the flower bud stage, the suitable temperature for broccoli is 15-18°C. If the temperature is unsuitable, especially if the temperature is on the high side and water and fertilizer are sufficient, the plants are prone to excessive vegetative growth, resulting in undesirable symptoms such as loose heads and deformities. When the temperature is above 24°C, broccoli is prone to forming loose heads, flowering and turning yellow, enlarged flower seeds, and deteriorated quality; above 30°C, the bud heads cannot form at all; below 8°C, the bud heads grow slowly. Therefore, attention must be paid to increasing wind protection and appropriate leaf shading to regulate the temperature well.
Supplement boron fertilizer to prevent hollow flower stems: Broccoli has special requirements for trace elements such as boron and molybdenum. Therefore, in addition to supplying the three major elements nitrogen, phosphorus, and potassium, trace elements should also be supplemented appropriately according to the plant's growth and development status, especially trace elements such as boron and molybdenum. During the flower head expansion stage, foliar spraying of 0.1% borax and 0.05%-0.1% ammonium molybdate solution can improve flower head quality and reduce hollow flower stems.
Harvest at the right time to prevent flower heads from loosening: Harvesting broccoli is relatively strict. Generally, it should be harvested after the flower head has fully grown, has a rounded surface, and before the edges open. Because at this time it is May, and the temperature is gradually rising, the flower heads grow and develop quickly. If harvesting is not timely, the flower heads are likely to loosen or even turn yellow, reducing marketability and quality. When harvesting, cut off the flower head together with 10 cm of the flower stem below it.
In addition, attention should be paid to early prevention of pests and diseases. When cultivating broccoli in spring, pests and diseases generally rarely occur. However, in the early stage under relatively high humidity, downy mildew is very likely to occur, and dimethomorph or propamocarb can be used for spray control. In the later stage of plant development, as the temperature rises, insect pests are very likely to occur and should be controlled early, mainly cabbage caterpillars, diamondback moths, and aphids, which can be controlled with spinosad, emamectin benzoate, and abamectin.