What are the propagation methods for potted fingered citron?

  Fingered citron is a variety with a small annual usage, low market attention, and small medicinal market demand; supply has always been relatively sufficient and prices have been sluggish, but recently things have not been calm, with more buyers at the production areas and fast movement, and the market has risen noticeably, so potted fingered citron has naturally attracted the attention of quite a few merchants.

  Fingered citron is the fruit of the fingered citron, an evergreen small tree in the Rutaceae family. When the fruit ripens, its top splits on its own into finger-like sections, like a Buddha's open hand, hence the name. Fingered citron has the characteristic of being both medicinal and edible. The times and regions where fresh fingered citron can be seen are limited, especially the "golden fingered citron" of Jinhua, which is the most famous. There is no fresh fingered citron in the north, so dried fingered citron can be used.

  The propagation methods for potted fingered citron include the approach grafting method, the cut grafting method, the air layering method and the cutting method, etc. Each is explained one by one below.

  1. The scalp-covering approach grafting method

  In the first year, transplant the sown trifoliate orange seedlings with a 10-15 cm soil ball into pots; after they survive and the stem grows to 30 cm high, cut off the top to encourage the stem to thicken, and use it as rootstock. In June-July of the second year, carry out approach grafting. Cut off the main trunk 10-15 cm above the ground, place the rootstock seedling at a suitable spot close to the mother plant, and use a grafting knife to make two slightly outward-slanting cuts on the two sides near the rootstock cut, one long and one short, with the long cut 3 cm and the short cut 2 cm. Then cut a flat surface on the scion from bottom to top, slightly carrying wood, and make a return cut to remove a bit of wood; be sure not to cut through the bark layer above the cut, and the cut should be longer than the rootstock cut so as to cover the short cut on the rootstock. After aligning the cambium layers of the two, wrap them tightly with hemp fiber, then wrap a layer of plastic film outside to keep warm and moist. After 30-40 days they will heal, then cut them off from the mother plant and place them in a shady spot for 1 week, taking care to water appropriately.

  2. The cut grafting method

  The best time for cut grafting is from Qingming to Guyu. Use trifoliate orange as rootstock. Cut off the rootstock main trunk 5 cm above the ground, make a cut from top to bottom at 1/3 of the trunk, carrying wood, with the cut 3 cm long, then make a slanting cut on each side of the lower end of the scion to form a wedge, insert it into the cut rootstock, leave two buds at the upper end, align the cambium, wrap tightly with hemp fiber, and seal the joint with wet mud. Finally seal the scion with wet soil, and it can take root and sprout. When the grafted seedling grows to 30 cm high, pinch off the tip to set the trunk. Lift the seedlings and pot them in August, and place them in a shady spot for 3-5 days.

  3. The approach grafting plus cutting method for two plants from one

  First carry out approach grafting (the method is the same as above; after it survives, do not cut it off at the union, but keep the scion extending about 12 cm downward from the graft union, cut it away from the mother plant, and at the same time insert the lower end of the scion into a pot, firm the soil and water thoroughly. After that, manage it normally, and when the roots have developed well, cut it off below the approach graft union, and you can obtain one approach-grafted plant and one cutting plant.

  4. The air layering method

  Choose a vigorously growing overly tall branch or a branch that has already set fruit firmly, make an upward slanting wound from below on the branch, deep to the pith, place the wounded branch into a felt tube, tie the lower part tightly, fill the tube firmly with soil, tie the upper part tightly, and set up a support. Water every day. When the temperature is high and moisture is sufficient, roots can form in 20-30 days. May-July, when temperatures are high, is the suitable time for air layering. If the layered branch has fingered citron fruit on it, you must wait until the fruit ripens and turns yellow, about 90 days, before cutting it away from the mother plant.

  5. The cutting method

  The best time for cutting is May-June. Choose branches that are well developed, growing well, and free of pests and diseases, cut them 12 cm long with 3-4 buds. Insert them 7-8 cm deep, leaving two buds exposed, firm the soil, and water thoroughly. Set up shade during the day and remove it at night, or cover with branches, leaves and weeds; in dry weather water every day, and roots will form in about 1 month. After the cuttings survive, water once every 7-10 days, move them into pots before Frost's Descent, and move them indoors to overwinter.

  Fingered citron is mainly propagated by cutting. The cutting time varies from place to place, but is always when the young buds are sprouting. In the lower reaches of the Yangtze River it is April-June, in Sichuan and Guangdong it is March-April or July-September, and in North China it is around the Start of Summer. Do not use water sprouts for cuttings; select strong spring shoots or autumn shoots from the previous year, cut the middle section, about 20-25 cm long, as the cutting, with 3-5 buds, remove the leaves and keep the petioles, and insert straight into the seedbed. The insertion depth is about half the total length of the cutting. After insertion keep it moist, build a shade in summer, and cover with grass and soil in winter for protection. After 9-10 months, the seedlings can be about 30 cm high, and they are planted in the ground the next year at Qingming.