Detailed Explanation of Key Techniques for Growing Loofah in Greenhouses

Loofah is an annual climbing vine plant of the genus Luffa in the Cucurbitaceae family. It is widely cultivated in temperate and tropical regions around the world, and is commonly grown in both northern and southern parts of our country. The fruit is one of the common vegetables, and when mature, the reticulated fibers inside can replace sponges for washing stoves and furniture. It is used medicinally for its effects of cooling, promoting diuresis, invigorating blood, promoting menstruation, and detoxifying. Let us now take a look at greenhouse loofah cultivation techniques!

Loofah Seedling Raising Methods

1. Variety selection: For greenhouse loofah, it is advisable to choose varieties that are tolerant to low temperature and weak light, fond of fertilizer and water, of high quality, early maturing, high yielding, with good marketability, and suitable for the market, such as Jiangshu No. 1, Jiangshu Meat Loofah, Taizhou Fragrant Loofah, etc.

2. Seed soaking and disinfection: Before soaking loofah seeds, sun-dry them for 2-3 days. For disinfection, soak seeds in 10% trisodium phosphate for 20 minutes, then soak in warm water at 60-70°C for 10-15 minutes while stirring constantly. When the water temperature drops to 30°C, continue soaking for 4-6 hours.

3. Germination method: After soaking and disinfecting loofah seeds, remove them and place them under conditions of 28-30°C for germination. Rinse with clean water 1-2 times daily, including the clean gauze used to wrap the seeds. After about 3-4 days, when the seeds show white sprouts, they can be sown.

4. Sowing method: Loofah has a relatively low transplant survival rate, so direct sowing is generally adopted. Sow 2-3 seeds per hole at a depth of 1-2 cm, with seeds placed flat. The ideal field water holding capacity is 75%. If too dry, water lightly. After sowing, cover with dry grass to preserve warmth and moisture.

5. Seedling stage management: Loofah generally germinates completely within 4-6 days. After seedlings emerge, appropriately lower the temperature. If moisture is insufficient during the seedling stage, water or spray appropriately, and also pay attention to pest and disease control. When seedlings grow 2-3 true leaves, they can be transplanted.

Loofah Planting Methods

1. Land selection and preparation: For loofah production, choose sandy loam with deep soil layers, fertile soil, convenient drainage and irrigation, and a neutral to slightly acidic pH value. Avoid poor, thin soil. During land preparation, generally broadcast 50-100 kg of lime per mu to adjust soil pH.

2. Timely transplanting: Choose sunny days for transplanting loofah. Before transplanting, apply sufficient base fertilizer, generally using 5000 kg of high-quality farmyard manure, 80-120 kg of superphosphate, and 25-30 kg of urea per mu. Then deep plow 20 cm, level with a rake, and build beds. Plant about 2800 seedlings per mu.

3. Temperature control: Within 2 weeks after transplanting loofah, maintain the greenhouse temperature at 30-33°C to help with seedling recovery. After recovery, lower the greenhouse temperature, maintaining daytime temperatures at 25-30°C. When exceeding 32°C, open ventilation ports for wind protection and cooling. Maintain nighttime temperatures at 20-25°C.

4. Trellis construction: Loofah cultivation must have a trellis. Bamboo, wood, or cement poles can be used as posts, with a trellis height of about 2 m. The top of the trellis is woven with small nylon ropes in crisscross fashion into squares. It must be able to withstand the weight of fresh gourds and strong winds and rainstorms.

5. Fertilizer and water management: Loofah has a relatively high fertilizer demand. Apply the first heavy fertilizer combined with earthing up during vine elongation, apply the second heavy fertilizer during peak fruiting, and apply 3-4 supplementary fertilizer applications in the late fruiting stage, applying 10 kg of NPK compound fertilizer or 20 kg of cake fertilizer per mu.

6. Plant adjustment: During the peak growth period, loofah plants close their rows and the field becomes crowded. Timely remove side vines, tendrils, male flowers, old leaves, and diseased leaves. Adjust the position of the main vine in an “S” shape to facilitate ventilation and light penetration, concentrate nutrients, and increase yield.

7. Artificial pollination: For loofah, generally choose 7:00-9:00 for artificial pollination. Use a brush to dip pollen and apply it to the stigma of female flowers. After flowering, apply 2,4-D at a concentration of 20-30 mg/L to the top of the fruit. Use lower concentrations at high temperatures and vice versa at low temperatures.

8. Timely harvesting: Loofah has strong continuous fruiting ability, and fruits grow quickly during peak fruiting. If planted properly, it can be harvested every 2-3 days. Harvest in the morning, cutting from the fruit stalk with a tool. Do not pull by hand to avoid breaking branches and vines.

Loofah Pest and Disease Control

1. Loofah Cottony Rot

[Damage] The damage period of loofah cottony rot is divided into the seedling stage and the fruiting stage, causing fruit rot after infection.

[Control] Focus on agricultural control, emphasizing the three-ditch system, reducing field humidity, and balanced fertilization. Avoid excessive or one-sided application of nitrogen fertilizer. For chemical control, spray with 1:2:200 Bordeaux mixture. During the fruiting period, when there is much cloudy and rainy weather with high humidity, prevent early and frequently.

2. Loofah Downy Mildew

[Damage] When the disease occurs, large numbers of leaves wither and die, directly affecting the yield and quality of loofah sponge.

[Control] For agricultural control, appropriately increase phosphorus and potassium fertilizer. When the disease first appears, timely remove diseased leaves. For chemical control, optionally use 500x metalaxyl for early root irrigation. At the initial stage of disease, spray with 2000x mefenoxam, once every 7 days, for 1-2 consecutive applications.

3. Loofah Viral Disease

[Damage] Loofah viral disease can be transmitted through aphids, farming operations, and contact with sweat.

[Control] Select disease-tolerant varieties, cultivate disease-free strong seedlings, transplant appropriately early, and timely control aphids. At the early stage of disease, spray with 20% Virus A wettable powder 500x solution or 5% Jun Du Qing water agent 500x solution.

4. Loofah Phytophthora Blight

[Damage] The pathogen originates from seeds or soil, and spreads through wind, rain, and irrigation water.

[Control] Select disease-resistant varieties, practice crop rotation, and choose fields with moderate elevation and convenient drainage and irrigation. At the early stage of disease, spray with 40% phosethyl-Al 200x solution or 75% chlorothalonil 500x solution, once every 7 days, for 2-3 applications.

5. Loofah Powdery Mildew

[Damage] The pathogen overwinters on diseased plant debris. During the growing season, large numbers of conidia are produced on lesions and spread by wind and rain. July to August is the peak period of disease occurrence.

[Control] In late June, spray once with 1:1:200 Bordeaux mixture for prevention. In early July, spray with 25% triadimefon 500x solution once every 5-8 days, for 2-3 consecutive applications.

6. American Leafminer

[Damage] Larvae mine and feed on leaf mesophyll inside leaves, forming curved white tunnels, affecting normal plant growth. In severe cases, it can cause large numbers of leaves and flowers to drop, and premature plant decline.

[Control] Clean the field. When sporadic damaged leaves appear in the field, timely remove them. Control agents include 0.25% Sheng Bang 1500x solution or 1.0% Abamectin 1500x solution. Note to rotate and alternate their use.