Paeonia Suffruticosa: The Blooming Beauty of Young Peony Flowers

Paeonia suffruticosa is one of the most beautiful varieties of peony, and the youngest among the four renowned peonies. It is well-known for its rich fragrance and propensity to bloom.

It produces single, semi-double, and double-flowered varieties, and some plants can even produce all three types on the same tree. Thanks to its distinct advantages, Zhao Pink, along with Yao Yellow, Wei Purple, and Dou Green, is considered one of the four great peonies.

I. Basic Introduction

Paeonia suffruticosa is a deciduous shrub. Its medium to tall stature is expansive. The plant has short and thick branches, which are soft and curved. The annual branches are long and light green.

Its leaves are usually twice or thrice pinnate compound leaves, with terminal leaflets being broad ovate. The leaf surface is green and hairless, while the back is light green, sometimes with white powder, and sparsely short hairy or nearly hairless along the veins.

The flower is solitary at the branch apex with five unequal bracts; five green, broad ovate and unequal sepals; and double corolla crown-shaped petals, which sometimes present in lotus, gold ring, or cassia shape. The large bud is round and pointed; the flower is pink. Flowering period is May; fruiting period is June.

Among the four renowned peonies, Zhao Pink is the youngest. Renowned for its rich fragrance and propensity to bloom, the plant can produce single, semi-double, and double petals. Some plants can even produce all three types of petals on the same tree.

Because of its distinct advantages, its reputation spread far and wide. Together with Yao Yellow, Wei Purple, and Dou Green, it is one of the four great peonies. This horticultural variety is cultivated for ornamental purposes.

II. Characteristics

Zhao Pink is a deciduous shrub. Its medium to tall stature is expansive. The branches are short and thick, soft and curved, with long annual branches that are light green and have long internodes; the scale buds are round and pointed.

The medium-long leaves are soft and sparse. The leaves are usually twice or thrice pinnate compound leaves, with the occasional three leaflets near the branch apex.

The terminal leaflets are broad ovate, measuring 7-8 cm long and 5.5-7 cm wide, divided into three segments at the middle, segments not divided or 2-3 shallowly divided.

The leaf surface is green and hairless, while the back is light green, sometimes with white powder, and sparsely short hairy or nearly hairless along the veins. The petiole is approximately 9 cm long, thick and soft, flatly extended.

The leaflets are long ovate or long elliptical, notched shallowly, sharply pointed at the end, with edges rolled upwards, leaf surface yellow-green.

The flowers are crown-shaped, sometimes presenting in lotus, gold ring, or cassia shape. The large bud is round and pointed; the flower is pink; flower diameter is 18 cm x 8 cm.

The outer petals are large and thin with 2-3 rounds; the inner petals are soft and delicate, neat, with a pink base, often interspersed with stamens; pistils are reduced, smaller, or petal-like, occasionally setting fruit.

The pedicel is thick, long and slightly soft, with the flower opening sideways. It is a medium flowering variety.

The anthers are oblong, 4 mm long; the disc is leathery, cup-shaped, purplish-red, with several sharp teeth or segments at the top, completely wrapping the carpels and splitting when the carpels mature; there are 5 carpels, rarely more, densely hairy.

The follicles are oblong, densely covered with yellow-brown hard hairs. The flowering period is May; the fruiting period is June. It is a vigorous grower with a high flowering rate. The flower shape is full, with many buds and a high root yield. It is a traditional variety.

III. Living Habits

This plant thrives in warm, cool, dry environments with ample sunlight. It enjoys sunshine, tolerates semi-shade, cold, drought, weak alkali, but dislikes waterlogging, heat, and direct sunlight.

It grows best in loose, deep, fertile, high and dry, well-drained neutral sandy loam soil. Growth is not good in acidic or heavy clay soils, with a pH of 6.5-7 being ideal. Ample sunlight is beneficial for its growth, but it cannot withstand the intense summer sun.

When the temperature is above 25°C, the plant will enter a dormant state. The optimum flowering temperature is 17-20°C, but before flowering, the plant must undergo low-temperature treatment at 1-10°C for 2-3 months.

It can withstand a minimum temperature of -30°C, but in cold northern regions, appropriate cold protection measures should be taken in winter to avoid frost damage.

IV. Cultivation Method

Planting: The soil should be loose, fertile, neutral to slightly alkaline. Trim the broken and diseased roots of the peony seedlings to be planted, soak them in insecticide and fungicide, and place them in a pre-prepared pot or hole.

The root system should be spread out, fill the soil to more than half of the pot or hole, lightly lift and shake the seedlings, compact the soil firmly, and make sure the root stem is slightly below the pot surface or ground level.

Watering: Water thoroughly after planting. Peonies dislike waterlogging and should be watered judiciously during the growing season. In dry northern areas, water should be given before flowering, after flowering, and before the ground freezes.

For potted plants, to facilitate management, cut off the withered flowers after blooming and bury the pot underground.

Fertilizing: After a year of planting, fertilize in autumn, mainly with mature organic fertilizer. It can be combined with soil loosening, surface application, or hole application.

In spring and summer, use more chemical fertilizer, combined with watering before and after flowering. For potted plants, liquid fertilizer can be applied with watering.

Pruning: In the year of planting, it is common to cut back. After spring sprouting, leave about five branches and remove the rest to concentrate nutrients and produce bigger, brighter flowers the following year.

In autumn and winter, in combination with garden cleaning, cut off dry flower stems, weak and flowerless branches. For potted plants, trim to desired shape as needed.

Hoeing: During the growing season, timely hoeing should be done, pull out weeds, and watch out for diseases and pests. In autumn and winter, turn the soil for peonies that are two years and older.

Repotting: When a potted peony has grown for three or four years, it needs to be repotted in a larger pot with new fertile soil in autumn, or divided and planted separately.

Spraying: Spray with lime sulfur before spring budding, and use a mixture of insecticide and fungicide in summer, depending on the disease situation, once every two weeks. This can be combined with fertilizing, adding chemical fertilizer and growth regulators as needed.

Forcing: To increase the number of flowers for holidays or celebrations, depending on the variety, the peony can be heated about 50 days in advance, with the temperature controlled at an average of 15°C between 10-25°C.

In the early stages, keep the plant moist, after budding, ensure good ventilation and light, and after budding, control the temperature according to the flowering period. Regular foliar fertilizing should be done, ensuring adequate water supply. This way, flowers can be seen in both winter and spring.

Viewing: A single peony plant naturally blooms for about 10-15 days, shortening with rising temperatures, but can last for a month at 3-8°C. For large-scale planting, temporary sheds can be erected to block wind and light to extend the viewing period.

For potted plants, move to a place where the sunlight cannot directly hit, a temperature of 5-10°C, a well-ventilated and well-lit environment, water appropriately according to the appearance and moisture content of the pot soil, do not water the flowers, this way the flowering period is the longest.

When cutting flowers for arrangement, the cut should be made in water or scorched for the best results. The water for arranging flowers should contain preservatives or a little sugar to prolong the blooming time of the cut flowers.

V. Propagation Method

Division

The specific method of propagation by division involves uprooting a hardy, thriving peony plant in its entirety and separating it at the intersection of the root system. The size of the original plant determines how many divisions are made: larger plants yield more divisions, smaller ones fewer.

Generally, each division should have 3-4 branches and a complete root system. After division, a small amount of sulfur powder and mud are used to coat and smooth the wounds on the roots before replanting.

The ideal time for division propagation is from the autumn equinox to the first frost of the year. At this time, the air and soil temperatures are high, the peony is in a state of semi-dormancy, but there is still a considerable period for nutritional growth.

If division planting is too late, the root growth of the year is very weak, or no new roots occur. In the spring of the next year, the plant is weaker, the roots are weak and not drought-tolerant, and it is easy to die.

If division is too early, the air and soil temperatures are high, rapid growth can occur, which can lead to autumn sprouting.

Generally, the mother plant for peony division is a robust clump. As much of the root system as possible should be retained on the mother plant used for division propagation, and all the roots on the new shoot should be retained, so that it can be divided into more new shoots after growing for 5 years.

Such plant seedlings are easy to survive and grow more vigorously. The more roots are retained, the more vigorous the growth.

Grafting

Grafting propagation of peonies is divided into two types, depending on the rootstock used: one is wild peony; the other is Paeonia lactiflora. The commonly used grafting methods for peonies are inlay grafting, belly grafting, and bud grafting.

Inlay grafting: Paeonia lactiflora is used as the rootstock because its roots are soft and heartless, easy to graft, thick and short, with sufficient nutrients, and vigorous growth after grafting.

If peony roots are used for grafting, the wood is harder, making grafting more difficult, but the lifespan is longer. The best time for grafting is usually from late September to early October each year. The rootstock is a robust and disease-free Paeonia lactiflora root, 2-3 cm in diameter and 10-15 cm long.

Belly grafting: This method is used to improve the variety of high grafting and head changing. It uses inferior peonies or 8-10 years old medicinal peony plants with many branches to graft into excellent varieties of different colors. The grafting time is from early July to mid-August.

First, select peony plants with excellent varieties, robust growth, and no diseases or pests. Cut the soil shoots that come out from the ground or short branches that are 5-7 cm long and have 2-3 robust buds. Leave a leaf stalk on the scion.

After selecting the scion, cut a horse-ear shape on the back of the bud at the bottom of the scion, and then cut a wedge shape on the other side of the horse-ear shape to make the grafting contact the cambium between the xylem and the phloem on both sides for easy survival.

Before and after belly grafting of peonies, except for not watering during the rainy season, maintain the appropriate humidity for normal growth of the plant. Bud grafting is an effective method for peony propagation and cultivation of multiple varieties and flower colors on one plant.

Bud grafting: It is carried out between May and July. It is better to graft on a sunny day. There are two methods: bark grafting and bud exchange.

Bark grafting involves cutting a rectangular or shield-shaped cut on the current year’s branch of the rootstock along with the xylem, and then cutting a bud block of the same size and shape from the axillary bud of the scion along with the xylem.

Then quickly attach the bud block to the cut of the rootstock and tie it tightly with plastic rope.

Bud exchange involves removing the axillary bud at the grafting site of the rootstock along with the cambium, leaving a complete bud embryo on the xylem, and then peeling off the axillary bud of the scion in the same way, quickly fitting it on the bud embryo of the rootstock, making sure they align, and finally tying it tightly with plastic rope.

The grafted plants should be watered, the soil loosened, and fertilized in time to promote healing.

Cutting Propagation

Cutting propagation is a method of reproducing new plants using the peony’s branches, which easily grow roots. This method is a type of asexual reproduction.

It involves cutting off the branch for propagation, separating it from the parent plant, and then inserting it into soil or other substrates to allow it to take root and become a new plant.

The branches used for peony cutting propagation should be selected from the current year’s soil bud branches emitting from the peony’s root, or branches with full, disease-free tip buds and a well-developed stem.

These selected branches are usually 10-18 centimeters long. Peony roots are fleshy and prefer high and dry environments; they are drought-resistant and dislike humidity.

Therefore, the nursery bed should be located in a sunny, well-ventilated area and raised high for seedling cultivation. When inserting the cuttings, water each row thoroughly after planting.

VI. Value and Other Aspects

Plant Culture

“Zhao Fen” is one of the precious varieties of peonies, named for its pink color. It has various flower shapes, robust plant growth, and a large number of fragrant flowers, making it a multi-flower variety.

Artists have captured the beauty of “Zhao Fen” within the small frame of a postage stamp. The “Zhao Fen” depicted by the artist blooms innocently and brilliantly, and the tension and wildness between the flowers and leaves express a sense of limitless freedom in life.