Key Points of Peony Planting and Cultivation Techniques: Methods to Extend Peony Blooming Time

Peony flowers are large and fragrant, hence they are also known as "heavenly beauty and national color." Peonies have always been loved by people, and if they are made to bloom during festivals such as New Year's Day and the Spring Festival, they will be even more popular. To extend the peony blooming time, one must master the key points of peony planting and cultivation techniques.

1. Variety Selection

There are many varieties of peonies, but not all varieties can be used for forcing blooms. Varieties with pure colors, easy forcing, and early blooming should be selected, mainly in bright red, orange-red, and pinkish-white varieties. White varieties suitable for summer forcing include 'Huhong', 'Luoyang Hong', 'No. 18', 'Yanzhi Hong', 'Huolian Jindan', 'Qinglong Wo Mochi'; pinkish-white varieties include 'Zhao Fen', 'Erqiao', 'Fen Zhong Guan', 'Fen He Mian', 'Si He Lian', etc.; the yellow variety 'Yao Huang' can also be used.

2. Plant Selection

Plants that are 4-5 years old, with many plump flower buds, and free of pests and diseases should be selected. For peonies used for summer forcing, management should be strengthened starting from the Spring Festival of that year, with attention to watering, fertilizing, and pest and disease control. During dry periods, water 4-5 times; in May, July, and September, apply 1 application each of fully decomposed cake fertilizer, 150 grams per plant each time, and use 0.1% potassium dihydrogen phosphate for foliar feeding 2-3 times. From May to June, spray 0.5-degree Bordeaux mixture on the leaves once every half month. In addition, for peonies used for summer forcing, it is best not to let them bloom and set seed during the Spring Festival of that year, to avoid increasing nutrient consumption and to benefit flower bud differentiation.

3. Potting

Before forcing blooms, peonies must undergo low-temperature conditioning at -2°C to 0°C to bloom easily; otherwise, even if placed under low temperature and given sufficient water and fertilizer, they will not sprout. To make peonies bloom on New Year's Day or the Spring Festival, they must undergo low-temperature treatment for more than 30 days. Also, peonies need 35-40 days from potting to blooming. If they are to bloom at the Spring Festival, the potting date must be calculated well, because the Gregorian month and date of the Spring Festival differ each year.

When potting, the peony should be dug out with a soil ball, and damaged and excessive "soil buds" (short buds emerging from the ground) should be cut off, then planted in a flower pot with a diameter of 40 cm and a depth of 25 cm. After filling and firming the pot soil, immediately water thoroughly once, place outdoors to acclimatize the seedlings for 4-5 days, then move indoors.

4. Greenhouse Maintenance

(1) Greenhouse

Adjustments should be made according to the natural rise in temperature and the day-night temperature difference during the spring peony blooming season. For newly potted plants, the room temperature should be kept at 10°C-13°C, rising to 18°C-25°C after one week. If the room temperature exceeds 30°C, open windows for ventilation and cooling.

(2) Water

After peonies are moved indoors, when the temperature rises to 18°C-25°C, water once every 1 day. Spray water on branches and leaves 2-3 times daily. If the peony has begun to leaf out and the flower buds have grown to the size of a thumb, increase leaf spraying and water less in the pot, to avoid excessive leaf growth that competes with flower buds for root nutrients and results in small flowers and dense leaves.

(3) Fertilizing

For peonies forced in summer, the roots have already accumulated a small amount of nutrients sufficient for sprouting, leaf unfolding, and blooming, so generally no excessive fertilizing is needed in the pot soil; only a little dilute cake fertilizer water is sufficient. To make peony leaves green and flowers vivid, use a 0.1% potassium dihydrogen phosphate solution for foliar spraying 2-3 times.

(4) Light

To make peony leaves green and flowers vivid, the greenhouse must also have sufficient light. The greenhouse used for forcing should have good light transmittance and supplemental lighting. A 40-watt fluorescent lamp can be installed above the peony plants at a distance of 1.5 m from the leaves, extending and supplementing light for 2-3 hours daily.

For peonies that have not sprouted 1 week after being moved indoors, apply 100 ppm gibberellin to the buds to break dormancy and promote sprouting. If the above methods are followed, peonies can sprout 5-7 days after being moved indoors, begin leaf unfolding after 10 days, flower buds swell after 15 days, flower buds show color after 30 days, and reach initial blooming in 35-40 days. At this time, if it is still far from the scheduled viewing period, lower the room temperature to 8°C-15°C to slow the blooming rate, and then raise the temperature at the viewing period to make them open.

Key Points of Peony Division Propagation Techniques

Timing for Peony Division Propagation

Peony is a clustered shrub and is very suitable for division, but division should not be too early or too late. If divided too early (before mid-September), because the temperature is still high, it easily causes terminal buds to sprout and consume nutrients, affecting growth and flowering the following year. If divided in spring, because the weather gradually warms and peonies sprout rapidly, they need to consume large amounts of water and nutrients, but after division the root system has not yet healed, so water and fertilizer cannot be supplied, not only causing failure to bloom that year but also leading to weak growth and affecting flowering the next year. If division is too late (after the Start of Winter), because the temperature is low, root wounds are difficult to heal, new roots cannot sprout that year, and in the second spring when sprouting and blooming require large amounts of water and nutrients, the roots have not yet grown or have grown very few, making it very easy for insufficient water and fertilizer supply to cause the plant to wilt and die. Practice has proven that the best time for peony division is late September to mid-October. Peonies divided and planted during this period have root wounds that heal easily and can quickly grow some new roots, which is very beneficial for flowering and rejuvenation the following year.

Peony Division Propagation Techniques

When dividing, select robust four- or five-year-old plants as mother plants, dig the entire plant out of the soil, and keep the root system as intact as possible. If there are broken roots, torn roots, or poorly growing blackened roots, cut them off with sharp scissors; gently shake off the soil attached to the roots of the dug-out peony seedlings and place them in a cool place to dry for two or three days. After the roots have dried and softened slightly, choose a part of the plant convenient for division, split it by hand or with a sharp knife into several clumps. Each clump should have three or four branches and two or three root systems. Apply charcoal powder to the wounds for antisepsis, then plant.

Whether planted in the ground or in pots, choose well-drained and relatively fertile sandy loam. Leaf mold, garden soil, and fine river sand can be mixed and disinfected with pesticide before use; place the divided and trimmed plant into a hole or pot, and evenly add the prepared culture soil; when the soil reaches 1/3 of the hole depth or pot depth, gently lift the plant two or three centimeters so that the roots can extend freely and the culture soil can penetrate into the root zone and closely contact the soil. The planting depth should preferably be the same as the plant's original planting depth, with the root crown just emerging from the soil surface; it should not be too deep or too shallow. If planted too deep, the plant often grows poorly, leaves turn yellow, and the root system is prone to rot; if planted too shallow, the root crown is exposed, affecting root growth and sprouting, and it is also not resistant to drought and severe cold. Water the planted peony promptly to ensure thorough watering to settle the roots, so that the root system and culture soil fully contact.

In cold northern winter regions, peonies planted in the open after division should be protected against cold, and measures such as mounding soil around the root crown or wrapping with straw bundles can be taken to resist the cold. Newly planted peonies must not be fertilized; only after they gradually rejuvenate may they be fertilized, otherwise it will be counterproductive and easily cause peonies to wilt and die from fertilizer damage.

When Do Peonies Bloom and How to Extend Peony Blooming Time

Peonies have thousands of years of natural growth and more than 1,500 years of artificial cultivation history. Many people do not know when peonies bloom. Below let us take a look together at when peonies bloom and how to extend peony blooming time.

When do peonies bloom:

Like other flowers, peonies also bloom in spring and summer, generally blooming in April to May, with the flowering period in May and the fruiting period in June. If you want to admire peony flowers, do not miss the time.

How to extend peony blooming time:

1. Prevent wind damage: When peonies bloom, it is the windy season in the north. Because their flower diameter is generally 15 cm to 25 cm, they are prone to being top-heavy, so after blooming, if there is strong wind, the branches are very easily broken, and strong wind also easily damages the delicate petals, causing the "dry edge" phenomenon. Therefore, during the peony flowering period, they must be placed in a sheltered place, and the flowering branches should also be supported with thin wooden sticks.

2. Sufficient light: Peonies need sufficient light during the flowering period. If light is insufficient, besides branches being prone to excessive growth and leaves being small and yellow, the leaves cannot carry out normal photosynthesis, so the flowers cannot get enough nutrients, resulting not only in small flowers but also in dull flower color and no fragrance.

3. Appropriate water: Peonies need more water during the flowering period than usual. Although spring temperatures are not high, it is windy and water evaporates relatively quickly, so giving the plant sufficient water is very necessary. According to the author's experience, during this period the pot soil should be kept moist (not waterlogged). When the pot soil is half dry, it should be watered. Usually in sunny weather with high temperature and sufficient light, water should also be sprayed on the plant leaves, but it must not be sprayed on the flowers, otherwise the flowers tend to fade early.

Peony Flowering Period Management Methods:

1. Cold protection: In the middle reaches of the Yellow River, peonies sprout in early February. Because early spring weather is changeable and prone to cold waves and late frost damage, special attention must be paid to cold protection. Potted peonies should be moved to a sheltered, sunny place; ground-planted peonies are best protected with a straw shed, or before frost, damp firewood and grass can be lit to produce smoke for frost protection.

2. Bud thinning: Peony flowering is similar to fruit trees bearing fruit, also showing an "on-year and off-year" phenomenon. After buds become visible, appropriate bud thinning should be carried out according to tree vigor and the previous year's flowering situation. If there are many flower buds that year, it can be regarded as an "on-year," and a portion of the smaller, lower-positioned flower buds should be removed (about one third). Bud thinning should be done earlier rather than later.

3. Pre-flowering foliar feeding: After peony leaves unfold, because photosynthesis strengthens, the leaves have a certain ability to absorb fertilizer. At this time, 0.1%-0.2% potassium dihydrogen phosphate can be used for foliar spraying. If sprayed 2-3 times before flowering, the flower buds can be fuller and larger, and the flowers more vivid.

4. Watering: In the north, spring is dry with little rain. In addition to watering once in early March, water thoroughly once more before flowering (early April). Near the flowering period, watering should be stopped. Do not spray water on leaves or flowers, otherwise it will shorten the blooming time and make the flowers fade quickly.

5. Shading: Peonies avoid strong wind and harsh sun when blooming. To extend the blooming time, when the flower buds first open, use thin white cloth (do not use colored cloth or flowered cloth) to shade them; this can extend the flowering period by 4-7 days.

6. Remove faded flowers: After peonies finish blooming, remove the faded flowers in time. This not only avoids the "declining" scene but also reduces nutrient consumption. Some single-petal varieties easily set seed; if not for hybrid seed collection, their flowers should also be removed in time.

7. Fertilizing after flowering: Because peony flowering consumes large amounts of nutrients, pre-flowering foliar feeding alone is far from enough to replenish them; after flowering, a relatively large amount of fertilizer must be applied to make up for it. It is best to use fully decomposed mixed fertilizer of the three cakes (sesame cake, soybean cake, cottonseed cake, or rapeseed cake). The amount of fertilizer should be determined according to the size of the plant. Fertilizing should be done at a certain distance from the root crown, by opening a ring-shaped shallow trench about 15 cm deep and applying it. Immediately water thoroughly after application.

8. Leaf disease prevention: After peony flowering, resistance to disease weakens, and brown spot disease easily invades. To protect the leaves from disease, after flowering spray Bordeaux mixture or 200-fold carbendazim suspension once every 7-10 days, continuously spraying 2-3 times. In this way, the leaves can suffer less damage throughout the year, allowing photosynthesis to proceed normally and accumulating more nutrients for flowering the next year.