A Detailed Guide to Propagation Techniques Every Pomegranate Grower Must Read
Pomegranate propagation methods include sowing, cuttings, root division, grafting and layering, but cuttings and sowing are the main methods.
1 Cuttings propagation
Nursery site preparation The seedling site should be chosen in a place with convenient transportation, capable of irrigation and drainage, deep soil layer, loose texture, and good water and fertilizer retention, in light loam or sandy loam. Level the ground, make a seedbed, and set aside for use.
Cutting period Spring, summer and autumn are all suitable. In spring, it is best done from late March to early April, and the cuttings should be 2-year-old hardwood branches. Summer and autumn cuttings are carried out in June-July and October respectively, and the cuttings should be semi-lignified branches of the current year.
Cutting collection From mother trees of pure variety, robust development, and the outer canopy of fruiting trees, select healthy, plump, strongly growing branches free of pests and diseases. Cut the branches into 8-15cm lengths, with the upper cut flat and the lower cut slanted. Dip the lower end of the branch into 95% industrial alcohol to remove substances such as tannins accumulated at the lower cut that are unfavorable for rooting and survival of the cuttings. Then soak the cuttings in running water for 5-10 minutes, and then soak the lower end of the branches in a GGR (green plant growth regulator) 50mg/L solution for 1 hour.
Insertion of cuttings Insert the prepared cuttings at a plant-row spacing of (8-10)cm×15cm, with the lower 1/2-2/3 buried in the growing medium. Press the soil on both sides of the cuttings firmly by hand, and water thoroughly once.
Post-insertion management The focus of management is to control air and soil temperature and humidity, try to keep the cuttings from losing water, and keep them in a fresh state at all times. The main measures are shading, moisture retention and cooling. ① Shading: generally a shading frame should be set up before cutting, and shade netting should be covered immediately after cutting. The light transmittance of the shade net should be 20%-30%. Curtains should also be hung on the east and west sides of the seedbed to block morning and evening sunlight. ② Moisture retention: immediately after cutting, set up a plastic arch shed. The plastic shed can regulate air and soil temperature and humidity to provide the best growing environment. In the early stage after cutting, the cuttings consume little water, so water once every 7-10 days. One month later, the cuttings begin to root and sprout, and water consumption gradually increases, so water once every 3-5 days. The amount of watering depends on soil moisture and air humidity. The best growing conditions for pomegranate: relative air humidity 80%-90%, and soil moisture maintained at about 80% of field capacity. ③ Cooling: the best soil temperature should be maintained at 20-25°C. If high temperatures occur, cooling must be carried out. There are three cooling measures: first, shading; second, ventilation; third, watering. At noon on hot sunny days in summer, promptly open both ends of the plastic shed to ventilate and cool; in the evening at 7-9 o'clock, after the temperature drops, close it tightly to maintain humidity. In addition, methods such as spraying water on the cuttings and watering on the plastic shed can also be used to cool down. ④ Fertilization: the fertilization principle is: apply thin fertilizer frequently. About 1 month after cutting, the cuttings root; after that, spray 0.25% urea on the leaves once every half month. Three months after cutting, the fertilization amount may be appropriately increased; water once a month with 3%-5% fishy water (made by adding 10 times water to discarded fish innards and the like, sealing for more than half a year), and rinse with clean water the next day; or apply 3% decomposed rapeseed cake once a month. ⑤ Weeding: promptly pull out weeds in the nursery site. When weeding, prevent disturbing roots and injuring seedlings. ⑥ Hardening: 3-4 months after cutting, appropriately extend ventilation and light time to improve the seedlings' ability to adapt to the external environment. ⑦ Transplanting: in the following spring, the cutting seedlings can be transplanted to the nursery site or planted in flower pots.
2 Sowing propagation
Pomegranate seeds have strong germination ability, and sowing propagation can obtain a large number of seedlings. Seed collection In August-September, harvest ripe fruits and take out the seeds, rub off the outer seed coat, dry them and store them, or mix the seeds with river sand at a ratio of 1:5 and store.
Sowing Sow in February-March. Before sowing, soak the seeds in 40°C warm water for 6-8 hours, and sow after the seed coat swells, so as to facilitate earlier germination. Sow the soaked seeds on the growing medium at a row spacing of 25cm, then cover with 1-1.5cm of soil, cover with grass, and water thoroughly once. After that, keep the pot soil moist and control the soil temperature at 20-25°C; after about 1 month, sprouts and roots will emerge.
Seedling stage management When the seedlings are 4cm high, thin them to a plant spacing of 6-9cm. In June-July, after pulling out weeds, apply one application of thin manure water; in August, apply one topdressing of phosphorus and potassium fertilizer. Protect against drought in summer and against freezing in winter. After leaf fall in autumn and before bud break in the following spring, carry out transplanting.