Key Techniques for Raising Tea Seedlings from Short Cuttings in Summer and Autumn
I. Nursery Plot Preparation
1. Site selection. A yellow soil in which tobacco, hemp or vegetables have never been grown is required; sandy loam or red soil may also be used; the soil pH should be 4.5-5.5, and the organic matter content in the 0-15 cm soil layer should be below 1.5%; watering should be convenient, and the site should be located below and near a water source.
2. Land preparation. First plow the soil deeply and thoroughly to 25-30 cm, then finely work the top 20 cm of soil repeatedly to ensure the soil is crumbled and the surface is level.
3. Bed making. In summer, make the beds oriented due east-west; in autumn, make them oriented slightly east-west. The beds should be 1.2 m wide and 8-10 cm high, with a 30 cm wide furrow between beds, and each bed should be 15-20 m long. After the beds are made, cover the top layer of each bed with fresh yellow loam to a thickness of 8-10 cm, then hoe it fine and rake it level.
4. Building the shade frame. Drive wooden stakes into the ground on both sides of the beds, with a stake spacing of 7.4 m to 1.7 m and a stake height of 45-60 cm above the bed surface. Connect the stakes horizontally with thin rods so that corn stalks can be placed on top for shade. If branches and other materials are used for shade, change the frame height to 40-45 cm, keeping the stake spacing unchanged.
II. Cutting Insertion
1. Preparation of cuttings. (1) Requirements: 33 cm long, stem diameter 0.3 cm or more, red-brown or semi red-brown, lignified or semi-lignified, leaves in the mature leaf stage, axillary buds swelling to the stage of 1 bud with 1 leaf just unfolding, and no serious pests or diseases. (2) Cutting the branches: after selecting suitable cuttings on the tea plant, begin cutting the branches. All slanted cuts should be at a 45 degree angle, in the same direction as the leaf slant, with the upper cut 0.2-0.3 cm from the nearest bud base; the cut branch should have 1 leaf and 1 growing bud, and be 2.7-3.3 cm long.
2. Inserting the cuttings into the soil. Two hours before insertion, water the nursery plot thoroughly, then hold the cuttings and insert them into the soil at a 45 degree angle, with a row spacing of 8-15 cm and a plant spacing of 1.4-7.6 cm, and a depth reaching the base of the leaf stalk. After inserting each row, press the soil firm with the hand promptly; after finishing 1 bed, fill and level the insertion furrow with loose yellow loam; after finishing 2-3 beds, water promptly and cover with corn stalks or branches.
III. Routine Nursery Management
1. Shading. From insertion into the soil to the appearance of primary roots is the first stage, with a shade level of 80%-45%; from primary roots to 1 bud and 3 leaves is the second stage, with a shade level of 75%-40%; from 1 bud and 3 leaves to the second round of tea seedling growth reaching 1 bud and 2 leaves is the third stage, with a shade level of 50%-75%; after more than 85% of the second-round tea seedlings have 1 bud and 2 leaves, choose a cloudy day to remove the shade material.
2. Watering. Based on weather conditions, inspect frequently and water cautiously, keeping the relative soil water content at 80% (first stage) and 75%-80% (second and third stages).
3. Topdressing. Begin topdressing when the first round of growth of the tea seedlings stops, and every 10-15 days apply 4.5 kg of urea evenly across the nursery plot per 667 sq m, then water repeatedly until the urea has completely dissolved into the soil, then stop watering.
IV. Lifting and Transplanting the Seedlings
For summer and autumn tea seedlings inserted from late May to mid-to-late August, the time to lift the seedlings is from February to mid-March of the following year. Before lifting the seedlings, the soil must first be watered thoroughly, so as to injure as few roots and leaves as possible and carry more soil, thereby increasing the survival rate after transplanting. If the seedlings cannot be transplanted promptly for several days, they can be kept in a container filled with 60%-70% muddy water, with the roots of the tea seedlings placed in the muddy water to retain moisture.