Detailed Explanation of Peony Planting Methods and Field Cultivation Management Techniques

Peony is one of China's traditional precious flowers, with a long history of cultivation and long been a symbol of great wealth and honor. With the continuous improvement of modern cultivation techniques, peony growing has become deeply integrated into daily life. Below, the editor of Huinong Network has compiled 5 field management techniques for us to study together.

1 Timely Hoeing and Loosening the Soil

Hoeing not only loosens the soil, improves air circulation, and prevents drought while preserving moisture, but also raises soil temperature in early spring. From early to mid-February to early March in spring, carry out the first hoeing and soil loosening. This hoeing should only loosen the soil around the plants to enhance air circulation and raise the temperature of the soil covering the peony buds. In late March and early April, carry out the 2nd and 3rd hoeings. The 2nd hoeing should be deep and thorough, leaving no unbroken soil, to prevent drought and preserve moisture, raise soil temperature, and promote early sprouting. The depth of the 3rd hoeing should be determined by soil moisture; be careful not to bruise or knock off the tender peony buds. After the peonies finish flowering, carry out shallow digging to a depth of about 15 cm. Afterward, if dry, hoe about once every half month to strengthen the plants' drought resistance. Once the rainy season begins, due to high temperature and abundant rain, soil moisture is high and weeds proliferate; at this time, hoe frequently and shallowly to speed up water evaporation, dry the soil as quickly as possible, and kill the weeds. After the Start of Autumn, hoe shallowly and thoroughly, eliminating weeds before they set seed to reduce damage the following year.

2 Fertilization and Irrigation

Starting from the 2nd year after planting, peonies are fertilized 2 to 3 times per year. The 1st application is carried out in mid-to-late March to ensure sufficient nutrients for new branch growth and flower bud development. After flowering, apply the 2nd fertilization to promote normal plant growth and flower bud differentiation. After the Start of Winter and before the ground freezes, carry out the 3rd fertilization. The 1st and 2nd fertilizations should mainly use high-quality organic fertilizer, generally applying 1,500 kg of dried manure or about 250 kg of cake fertilizer per 667 sq m; the 3rd application should use 3,000 to 5,000 kg of organic fertilizer per 667 sq m. Fertilization should be combined with irrigation. Peonies have the characteristic of preferring dry conditions and disliking wetness; in addition, their root system is well developed with strong water-absorbing capacity, and the fleshy roots can store large amounts of water. Under general drought conditions, irrigation is not needed. However, in particularly dry years, appropriate irrigation should be applied. The number of irrigations and the amount of water should be determined by the degree of drought and the age of the plants. 1- and 2-year-old plants have poor drought resistance; if the drought is severe, irrigate promptly. Plants 3 to 4 years and older also need irrigation in severe drought. Peonies should not be watered by flooding irrigation; instead, use the method of furrow infiltration irrigation. It is best to water with river water or pond water, because this water is warm and rich in nutrient elements, which benefits peony growth and development. In summer, irrigation should be done in the evening or early morning; in early winter and spring, watering should be done when the weather is warm. When the ground has not thawed, there is no need to water. If water accumulates in the rainy season, dig trenches immediately to drain it.

3 Plant Shaping and Pruning

Shaping and pruning can keep the plant with a balanced and appropriate number of branches and an attractive, symmetrical plant form, maintain the growth balance between the underground and aboveground parts, and concentrate nutrients to promote root growth and plump flower buds. Practice has proven that the quality and quantity of peony blooms, root growth, and plant lifespan are all directly related to whether shaping and pruning are done reasonably.

The shaping and pruning of peonies generally begins in the spring of the 2nd year after division and replanting, when the tender buds have grown to about 5 cm. For establishment, among the new clustered branches of the peony, select and retain several branches that are robust, evenly distributed, and well balanced in growth, and designate them as the plant's main branches. The number of retained branches should be determined by the size of the clump, variety, cultivation purpose, and growth vigor over the years. As the plant ages, the number of branches can also increase accordingly. In that year, a certain number of thick sprout branches can be selected and retained to develop into main branches. Generally, 5-year-old ornamental varieties can retain 10 to 12 branches; those 6 years and older can appropriately increase new branches. Each peony branch generally bears 2 to 3 flowering branches, alternating with each other, and below the flowering branches there are also several clustered branches and adventitious buds. To concentrate nutrients so that flowering branches grow robustly and flowers are large and brightly colored, 4- to 5-year-old peonies generally retain one flowering branch at the top of each branch; those 5 years and older can retain 1 to 2 evenly distributed flowering branches, and the rest should be pruned promptly. Excess leafy clustered branches and adventitious buds should also be removed. After flowering, the dry branches, damaged branches, diseased branches remaining on the upper part of the flower base, and excess lateral branches on the main trunk should also be pruned promptly.

4 Pest and Disease Control

4.1 Diseases

Common peony diseases include the following:

(1) Violet root rot. It is a fungal disease spread through soil. It occurs at the root collar and roots, and is more commonly seen at the root collar. In mild cases, dotted or patchy spots form, no new roots develop, branches are thin, leaves turn yellow, and buds are small; in severe cases, the entire root collar and root system rot and the plant dies. This disease mostly occurs in the high-temperature and rainy season from June to August. Control measures include: first, choose well-drained, high, dry sandy loam for planting; second, cultivate promptly in the rainy season to reduce soil moisture; third, choose disease-resistant varieties; fourth, soak the roots with fungicide at planting; fifth, disinfect affected plants promptly, and remove severely affected ones.

(2) Sclerotinia rot. Also called stem rot, the pathogen is Sclerotinia sclerotiorum. When it occurs, water-soaked spots appear on the stem near the ground, gradually expand and rot, and white cotton-like matter appears; it may also infect leaves and flower buds. Control measures include: first, choose well-drained, high, dry land for planting; second, promptly remove diseased plants when found and disinfect the soil; third, rotate once every 4 to 5 years.

(3) Brown spot. Also called red spot, it is transmitted by fungi and mainly infects leaves, and also harms new branches. In the early stage, brown spots the size of grains of rice appear on the underside of leaves, with slightly darker edges, forming irregular concentric ring-pattern dead spots that are darker outside and lighter in the middle, which merge and connect with each other, causing leaves to scorch and fall. Diseased leaves produce a dark green fuzzy layer; diseased stems and petioles produce raised lesions; the pathogen overwinters in the stems, leaves, and soil of diseased plants. Control measures include: first, around the Start of Winter, sweep up fallen leaves and burn them to eliminate the pathogen; second, before disease onset (in May), spray Bordeaux mixture at 1:1:160 to 200 times, about once every half month, until the end of July; 3, in the early stage of disease, spray 0.125% to 0.2% carbendazim, about once a week, for 3 to 5 consecutive applications.

Rust, anthracnose, and root-knot nematode disease also occur frequently. The control methods for rust and anthracnose are the same as for leaf spot. For plots where root-knot nematode disease occurs, apply 3 kg of 3% carbofuran granules mixed with soil per 667 sq m by broadcasting.

4.2 Insect Pests

(1) Underground pests. These mainly include cutworms, white grubs, and mole crickets. Poison bait made with wheat bran can be spread in the field in the evening to trap and kill them; fermented and thoroughly decomposed fertilizer can also be mixed with phoxim (apply 0.25 kg per 667 sq m) and turned into the soil to a depth of 20 cm.

(2) Aboveground pests. These mainly include scale insects and longhorn beetles. When pests are found, prune off the affected branches and leaves and burn them; during the larval hatching period, spray 0.067% to 0.1% omethoate; spraying 3-degree lime sulfur mixture during dormancy or before sprouting in early spring can effectively control scale insects. To control longhorn beetles, make holes at the root zone of the peony, 20 cm deep, and place one aluminum phosphide tablet in each hole.

5 Mounding Soil for Overwintering

Peonies are relatively cold-resistant. To avoid damage to peonies by humans and livestock in winter and the effects of strong cold air, it is best to mound soil around peonies of each year's growth for overwintering. After late October each year, sweep up and burn all fallen leaves on the ground, then dig soil from around the plant and mound it over. For 1- to 2-year-old peonies, they should be completely buried in soil; for 3- to 4-year-old peonies, the mounding height should be half the plant height; for those 5 years and older, mounding only up to the base is sufficient.

How to Manage Peonies: Detailed Monthly Management and Care for Peonies

January (Minor Cold, Major Cold) Average monthly temperature 0.4 degrees, average monthly precipitation 6.85 mm, soil temperature at 5 cm depth 1.1 degrees, soil temperature at 10 cm 1.6 degrees. Peonies are in the deciduous dormant period, and flower bud differentiation has been completed. Main work this month: (1) Pay attention to cold protection for field-grown peonies so they overwinter safely. (2) For field peonies forced for early spring flowering (blooming before the natural flowering period), begin setting up plastic greenhouses in the first ten days and carry out management. (3) Apply base fertilizer once.

October (Cold Dew, Frost Descent) Average monthly precipitation 46 mm, soil temperature at 5 cm depth 16.6 degrees, soil temperature at 10 cm 17.1 degrees. Autumn open-field forced peonies bloom successively. Main work this month: (1) Continue peony planting and propagation, and complete sowing, cutting, grafting, division, and layering (double flat method) before Cold Dew. (2) Pot potted peonies. Bury them together with the pots in soil in preparation for forcing. (3) After Frost Descent, begin removing peony leaves, and gather and burn all fallen leaves. (4) Pay attention to controlling pests on branches and trunks. (5) Prepare for peonies being sent to Guangzhou for forcing and manage plants for greenhouse forcing during the Spring Festival. (6) From late October, begin early-winter peony forcing, and set up greenhouses over field peonies.