How to sow Codonopsis pilosula seeds? A detailed guide to the latest sowing methods

Codonopsis pilosula prefers a mild and cool climate. For propagation, two methods are commonly used: direct seeding and seedling raising with transplanting, but direct seeding is preferable. For the seedling bed, choose a hillside field or abandoned land on a semi-shaded, semi-sunny slope, close to a water source, free of underground pests and perennial weeds. Choose new seeds. Let us take a look together at the sowing methods for Codonopsis pilosula seeds!

Sowing time for Codonopsis pilosula

1. Winter sowing: Sow between “Frost's Descent” and “Start of Winter”. The seeds do not need treatment that year; after being soaked by winter rain and snow, they emerge early the next year, grow vigorously, and have strong drought resistance. Because Codonopsis pilosula seeds are small, the soil covering must be shallow. If winter sowing encounters strong winds, the seeds are easily blown away, causing gaps in the seedlings.

2. Spring sowing: Spring sowing is best around “Spring Equinox”. The seeds need treatment. Select plump, mold-free seeds, put them in a cloth bag, place them in 40°C warm water, and rub them immediately for about half an hour, until no yellow water flows out. Take out the cloth bag, cover it well with a wet burlap piece, and place it in a 25-30°C location for germination. Wash once each morning and evening with 40°C water, keeping it moist. After 4-5 days, when the seeds germinate, they can be sown.

Sowing methods for Codonopsis pilosula

1. Drilling: In the prepared seedbed, open furrows about 1 cm deep at a row spacing of 15-20 cm. Mix the treated seeds evenly with fine sand, scatter them in the furrows, cover with soil and level it, press firm, then cover with 1 cm of fine sand.

2. Broadcasting: On the prepared seedbed surface, mix the seeds evenly with 10 times their volume of fine sandy soil, scatter evenly over the seedbed surface, rake once with an iron rake so the seeds combine with the soil, then level and press the seedbed surface, and additionally cover with 1 cm of fine sand. The seeding rate is about 1 kg per mu. Codonopsis pilosula can also be intercropped with corn, which can both shade the seedlings and serve as a support for the Codonopsis pilosula stems and vines. Strengthen field management to achieve a double harvest of grain and medicinal material.

Seedling-stage management of Codonopsis pilosula

1. Cultivation and weeding: After sowing, keep the seedbed moist. Seedlings emerge in about 9-13 days (if drought occurs, emergence takes longer). When the seedlings grow 2 true leaves, begin cultivation and weeding. Cultivate and weed shallowly to avoid burying seedlings or damaging roots. After the Codonopsis pilosula seedlings close their rows, stop cultivation and weeding; if weeds appear, pull them by hand to prevent damage to the Codonopsis pilosula seedlings.

2. Removing the cover: When Codonopsis pilosula seedlings have two pairs of true leaves and reach more than 1 cm, choose a cloudy afternoon and remove all the cover at once. Alternatively, when Codonopsis pilosula is 1.5 cm tall, first remove half the cover, and when the seedlings are 3 cm tall, remove all the cover. If there is a lot of rain in the early covering period, the cover is close to the ground and partly rotted, and most seedlings can pass through the cover, then there is no need to remove the cover; keep it covered until seedling lifting.

3. Proper thinning: For fields where seedlings grow densely, thin when the small seedlings grow to 5-7 cm. The minimum seedling spacing is about 1.0 cm, the average seedling spacing is 3.0-3.5 cm, and the density is preferably within 800-1000 plants per sq m.

4. Fertilizer and water management: Apply topdressing according to seedling condition. Urea and potassium dihydrogen phosphate, 50 g each, can be added to 10 kg of water and sprayed on the seedbed. Before the seedlings emerge and during the seedling stage, keep the seedbed surface moist. If excessive rainfall causes water accumulation, drain it promptly. In cases of severe drought, water promptly where conditions permit. Before the soil freezes, cover the seedling field with a small amount of fine soil (about 0.5 cm thick) to prevent winter soil cracks from damaging the seedlings.

5. Timely seedling lifting: Codonopsis pilosula seedlings overwinter in the field. After the soil thaws the following spring, lift the seedlings before transplanting, taking care to avoid root damage. The method for lifting seedlings is to first dig up the seedlings with a three-pronged iron fork, then gently turn them over, pick out the seedlings, shake off the soil, and tie the dug seedlings into small bundles of 400-500 g with 20% soil attached, put them into burlap bags or plastic woven bags, and transport them to the transplanting site for transplanting.

6. Planting, storage and transport: Generally, most Codonopsis pilosula production areas can raise seedlings. When transplanting, lift the seedlings and transplant them immediately. However, sometimes seedlings can be raised centrally in areas with irrigation conditions and then transported to other areas for planting. In this case, the lifted seedlings cannot be planted temporarily and need to be heeled in for storage.