The Latest Technical Guide to Propagating Selfheal (Prunella vulgaris)
Selfheal (Prunella vulgaris) is a common wild plant in southern China that grows along roadsides, on mountain slopes and in fields, and it is also a commonly used medicinal plant. It is a perennial herbaceous plant, with its seed-setting period between July and August. It has strong adaptability and tenacious vitality. At present it is mainly grown as a medicinal herb to create economic benefits. To grow it, you first need to raise seedlings; once seedlings are propagated, they can be planted out over a large area. At present the main propagation method is raising seedlings from seed, and another method is raising seedlings by division. The propagation methods are introduced separately below.
1. Seed selection and collection
If you are planting for the first time, you can buy seeds; when buying seeds, inspect the seed source on site and choose good, plump seeds. If you are planting for the second time, first select excellent, healthy mother plants of selfheal from which to collect seeds, taking disease-free, plump, mature seeds of normal color. Remove impurities, wash them clean, dry them in the sun and store them sealed.
2. Site selection and land preparation
For the seedling-raising site, it is best to choose land that is sheltered from the wind and facing the sun, with good light, convenient drainage and irrigation, and deep, fertile nitrogen-rich soil. Before building the seedbed, plow the whole field, then rotary till and fine till once, apply base fertilizer, and apply it over the whole field while fine tilling it in. Form ridges about 1.3 m wide, with furrows 20 cm wide and 25 cm deep, then spray once with a suitable concentration of validamycin fungicide, and sow only after drying in the sun for 3 or 4 days.
3. Sowing
Sowing is suitable in spring and autumn. Generally, for spring sowing, scrape about 2 cm of the surface soil off the ridge to make a level surface, then broadcast the seed evenly directly on the ridge, then cover the surface soil back over it; after covering evenly, water thoroughly so the seeds are pressed firmly against the soil. Then water every morning and evening, maintaining 65% moisture content to meet the seeds' germination needs. But do not water too much, for fear of lack of oxygen causing the seeds to rot.
4. Seedling stage
After the seeds germinate and emerge, the amount of watering can be reduced to avoid disease at the seedling stage, but they still must not lack water; after leaves grow, water more again, and also add some low-concentration compound fertilizer solution. When the seedlings have emerged evenly, promptly plant large and small seedlings separately to avoid competition for nutrients and to keep small seedlings from falling behind in growth. Also promptly pull out any weeds. One week before transplanting the seedlings, apply a top dressing mainly of nitrogen fertilizer with a small amount of phosphorus and potassium fertilizer; when transplanting, water thoroughly and transplant once the soil has loosened.
3. Propagation by division
Before growth starts in spring, dig up the old roots of previously planted plants, then divide and plant them. They can be planted and raised directly in the field, with a row spacing of 20 cm and a plant spacing of about 5 cm, using hole planting or furrow planting, but the planting depth is about 8 cm in both cases. Keep them moist at all times to promote rooting; after rooting, they will sprout in about one to two weeks.
Selfheal propagation mainly uses the two methods above, but at present sowing is the main method; raising seedlings from seed can preserve the plant's excellent characteristics, while division grows less well than sowing and easily carries diseases, though division is relatively fast. You can choose the propagation method according to your own needs.