when is the best time to plant roses

The best time to plant roses is March to April every spring. The climate at this time is suitable and the weather is warm, which is conducive to the rapid germination of rose seeds. Plants in good growth condition can bloom in May to June.
Generally, it is planted on the ground. It likes light very much, so when planting, you should choose a place with better light, so that it will grow more vigorously in the later period, and the flowers will bloom more beautifully if there is sufficient light.
The time for planting roses depends on the method: if you plant by divisions, it can be done in spring or autumn. If taking cuttings, do so in spring. If sowing, do so in the fall.

Rose belongs to the family Rosaceae, and is a deciduous shrub of the Rosaceae family. The branches and stems have many needles and odd-numbered pinnate compound leaves, with 5 to 9 leaflets, oval, and the back is densely covered with white hairs and edge thorns. The petals are obovate, double to semi-double, and the flowers are purple-red or white. The fruit period is from August to September, and they are oblate and spherical.

Soil preparation

Roses are perennial woody plants with a long production cycle. Cuttings can be harvested in 3-4 years after planting once, and grafted seedlings can be harvested in 5-6 years. In order to obtain high quality, high yield and high efficiency of cut flowers, the soil for planting roses must have good physical and chemical properties during the cultivation period. It is better to choose loose and ventilated muddy loam with low groundwater level. The soil needs to be rich in organic matter, and the content should preferably reach more than 10%. Soil pH is around 6.5.
Soil improvement should be combined with planting borders. Through deep plowing and application of a large amount of organic fertilizer, the permeability, water retention and fertility of the soil can be improved and maintained for a long time, and the long-term good growth of the rose root system can be promoted. Types of organic fertilizers that can be used to improve soil include cow manure, pig manure, sheep manure, chicken manure, bone meal, leaf mold, compost, etc.
The planting border should be 0.9m wide on the border surface, 0.5m wide at the bottom of the walkway, 0.5m high on the border, and the border surface should be flat. After the planting border is completed, the pH and EC value of the soil need to be checked again, and adjusted with fertilizer, acid, and alkali to adjust the pH value to around 6.5 and the EC value to 0.8~1.2mS/cm. If the EC value is less than 08 Adjust with fertilizer, and rinse with water if the EC value is greater than 1.2. Drip irrigation comes pre-installed.

Cultivation methods and colonization

Rose production mostly adopts branch-breaking cultivation method. The cultivation method is single border and double row cultivation. The spacing between plants is 12cm, the spacing between rows is 50cm, and 5000-6000 plants are planted per acre. Greenhouse cultivation can be used for planting all year round. When planting, straighten the planting to ensure that the planting rows are straight and the seedlings are easy to manage. The planting depth should be slightly deeper than the cutting depth, but the soil should not exceed the main bud of the seedling.
After planting, water enough for rooting in time. When planting in hot weather, pay attention to shade and cool down and spray water on the leaves. Within one week after planting, ensure that the root soil and topsoil are fully moist, spray water on the leaves during the day, and provide appropriate shade; gradually reduce the amount of watering on the leaves after 7 days, but keep the topsoil moist, and spray fungicides such as carbendazim or chlorothalonil. Carry out disease prevention and control once; gradually reduce the amount of soil watering after 15 days, and then water in a timely manner according to the dryness and humidity of the soil to keep the soil moist, and start using a drip irrigation system; enter normal management after 30 days.

Cultivation environment control

The cultivation environment of roses mainly includes environmental factors such as water, fertilization, temperature, humidity and light.

Moisture management

Use pollution-free river water, spring water or well water for irrigation. The watering time, frequency and amount of roses are affected by the season, weather, soil and plant growth conditions. Producers mainly determine based on production experience or instruments to continuously observe and detect soil moisture content, plant growth conditions, etc. The instrument can use a soil tensiometer to quickly measure soil moisture, use a tensiometer to monitor soil moisture, and create a reference basis for drip irrigation.
Water twice a day on sunny days (the soil moisture tension PF is maintained at around 1.8). Watering time should be chosen between 10:00 and 14:00. Do not water in the morning or evening to avoid lowering the soil temperature due to low water temperature; 4 The temperature in ~June is high and dry, and the cultivation soil is also drier. The growth of rose plants accelerates and water consumption also increases. Mainly increase the soil moisture by increasing the frequency of watering; the soil moisture tension PF is maintained at 1.6~1.8, and the watering time is selected from 10:00~16:00 on sunny days. Greenhouses without cooling facilities need to increase spray cooling and spray time. Choose 14:00 on a sunny day;
From July to September, the temperature is high, rainy, and humid, and the cultivation soil moisture is relatively high. However, rose plants grow very quickly and need to consume a lot of water. By increasing the amount of watering each time, the large demand for water for the growth of rose plants is met, and the soil moisture tension PF is maintained at 2.2; on cloudy days, in order to reduce air humidity and reduce the occurrence of pests and diseases, watering is only done once at 10:00. Stop watering when it rains continuously, and wait for the rain to stop and the weather to clear up before watering in time. This will help regulate and control the air humidity in the greenhouse. The weather in autumn is cool, which is more suitable for the growth of cut roses. Keep watering 1 to 2 times a day. Soil moisture tension PF remains around 1.8.

Fertilization management

Roses’ demand for macronutrients nitrogen, phosphorus and potassium is 3:1:2 during the vegetative growth phase and 3:1:3 during the flowering phase. Medium and trace elements can be applied regularly every month. Medium amounts of elements include calcium, magnesium, and sulfur; river water and well water contain higher amounts of calcium and magnesium, so no or less addition may be required during fertilization.
Among the trace elements, zinc and boron are relatively lacking, so attention should be paid to adding them during production. There is no shortage of iron in the soil, but the absorption of iron is related to the pH of the soil. When the pH value is 5.5 to 6.5, a small amount can be added; when the pH value is greater than 7, it is difficult for iron plants in the soil to absorb it. During production, soil nutrients should be tested regularly, and based on the test results, it can be judged whether the various nutrients in the soil can meet the normal growth and development of roses.

When various nutrients in the soil reach optimal values, better cut flower yield and quality can be obtained. Refer to the table below for optimal values. If the nutrients in the soil are insufficient or low, you can gradually increase the amount of fertilizer by 10% of the original amount each time until the optimal amount. If the nutrients in the soil are too high, you can reduce the amount of fertilizer or water it. Rinse. Roses have well-developed root systems, fast growth rates, and high flower yields. Therefore, they require a large amount of nutrients in the soil. Roses have diverse nutrient needs. Only when different types of nutrients are properly combined can we achieve high-quality flowers, high yields, and bumper harvests year after year. .

① Different types of nutrients have different effects on roses

Nitrogen fertilizer is an important nutrient required by roses and plays an important role in the nutritional growth of rose soul and flower yield. Only when there is an adequate supply of nitrogen fertilizer can the leaves flourish and grow normally. If there is insufficient nitrogen fertilizer, the rose branches will become thin, the leaves will turn yellow, and the new shoots will grow slowly. However, if there is too much nitrogen fertilizer in the soil, it will easily cause elongated branches, loose tissue, few flowers, and even deformed flowers.
Phosphorus fertilizer can promote the growth of rose roots, make the roots developed, the leaves thick, and the flowers brightly colored. If there is a lack of phosphate fertilizer in the soil, the branches will be weak and the flowers will droop and be weak. Therefore, when applying base fertilizer every autumn, an appropriate amount of phosphate fertilizer should be added.
Potassium fertilizer can promote the normal growth of new shoots and leaves of roses, increase the number of flowers, plump flower buds, and increase the content of rose oil in flowers.

In addition to the three nutritional elements of nitrogen, phosphorus and potassium, roses also need certain types of trace elements, such as iron, boron, manganese, zinc, etc. If there is a lack of trace elements in the soil, plant leaves will become chlorotic, and even plant organs will become deformed, causing various physiological diseases and affecting the normal growth and development of rose plants.

②Types of commonly used chemical fertilizers for roses and fertilization requirements

a. Urea. Urea is a nitrogen fertilizer commonly used in rose production, mainly as top dressing. Top dressing is generally applied in furrows and holes, and takes effect 5 to 7 days after fertilization. Watering should be carried out in time after applying urea. The dosage per mu is generally 10 to 15 kilograms. Urea can be applied 3 to 4 times a year. For sandy soil, attention should be paid to applying frequently and sparingly.
b. Ammonium bicarbonate. Ammonium bicarbonate, referred to as ammonium bicarbonate, is a quick-acting nitrogen fertilizer. It can only be used as top dressing, furrow application or hole application. It should not be broadcast on the ground because it evaporates quickly. It needs to be covered with soil in time and combined with watering. Fertilizer will take effect within 2 days after application. When applying fertilizer, do not let the fertilizer fall on the plant leaves and burn the leaves. The amount of fertilizer applied per acre is 10 to 20 kilograms, and topdressing can be done 3 to 4 times a year. This fertilizer is easy to dissolve and cause loss, so special attention should be paid to applying it frequently and sparingly. This fertilizer will not damage the soil structure and cause soil compaction when used for a long time, and is widely used in production.
c. Superphosphate. It is mainly used as base fertilizer and has slow fertilizer effect. In production, it is often mixed with soil fertilizer and used as base fertilizer in autumn. The main method is furrow application, and the dosage per mu is generally 30 to 50 kilograms. Superphosphate is easy to clump, so it should be fully crushed or mashed when used, otherwise it will burn the plant roots. In the late growth period of roses in autumn, 1% superphosphate extract can be used for foliar fertilization, and the effect is also very good.
d. Calcium, magnesium and phosphorus. The properties, usage and dosage of calcium magnesium phosphate fertilizer are the same as those of superphosphate, but calcium magnesium phosphate fertilizer is non-corrosive, non-hygroscopic, non-caking and easy to use, so it is widely used in production.
e. Potassium sulfate. Potassium sulfate has little mobility in the soil, so it can be used as base fertilizer or top dressing. It is best to apply it before rose budding, and the effect is remarkable. The more productive the rose garden is, the more potassium fertilizer is needed. Potassium sulfate is generally applied in ditches, with a general dosage of 10 to 15 kilograms per acre, and it can be applied once a year. Long-term use of potassium sulfate will cause soil compaction, so it is better to mix it into organic fertilizer as a base fertilizer.
Potassium sulfate is acidic and corrosive to a certain extent. Avoid contact with branches and leaves to cause burns. Potassium sulfate cannot be mixed with nitrogen fertilizer and superphosphate, otherwise the fertilizer efficiency will be seriously reduced. Potassium sulfate is very effective when used as foliar fertilizer before rose budding. The concentration is 0 or 5%. It is absorbed quickly and has obvious effects.
f. Potassium chloride. The properties, usage and dosage of potassium chloride are basically the same as potassium sulfate. Potassium chloride should not be used in saline-alkali areas.
g. Diammonium phosphate. Phosphoric acid secondary plating is a very good nitrogen and phosphorus compound fertilizer with long and high fertilizer efficiency. It is mainly suitable for use as base fertilizer and is mainly applied in furrows. The dosage per mu is 30 to 50 kilograms. When phosphoric acid secondary plating has been added to the base fertilizer, there is no need to add phosphate fertilizer.

h. Potassium dihydrogen phosphate. Potassium dihydrogen phosphate is a composite material of phosphorus and potassium. It has high solubility and is suitable for use as foliar fertilizer. The conventional concentration is 0.2% to 0.3%, and it is usually sprayed every 15 days. It can also be combined with spraying at the same time.

③ Fertilization time: The types of rose fertilizer include base fertilizer and top dressing.

a. Base fertilizer. Rose base fertilizer should be applied after the leaves fall in autumn, and the fertilization time should be as early as possible. Applying basal fertilizer early in autumn can not only heal the roots injured during trenching and fertilization and grow new roots, but also allow the applied soil fertilizer to be fully decomposed and decomposed in the soil, which is beneficial to promoting the vigorous growth of plants in the next spring. The specific time in the northern region should be from late September to early October. Applying basal fertilizer too late in autumn often affects the normal growth of plants in the next spring.
b. Top dressing. Top dressing of roses is carried out during the spring and summer growing seasons. The fertilizers applied are mainly chemical fertilizers, which are fast and highly targeted. The specific top dressing time can be divided into four periods: germination period, flower bud period, full flowering period and late flowering period. During these four periods, plants grow a lot and require a lot of fertilizer. Nutrients should be added to the soil in time to ensure flower production.
The fertilization experience of flower growers in the rose-producing areas of southern my country is: “three to five flowers are red” and “four water and three fertilizers are used to harvest all the flowers.” This means that from the time the roses begin to form flower buds to the time the flowers are completely harvested, they need to be watered 4 times and fertilized 3 times. This is enough to show that repeated application of chemical fertilizers during the rose blooming period is extremely important to the yield of flowers.

Temperature control

The optimal growth and development temperature for rose production is 24℃~26℃ during the day and 14℃~16℃ at night. When the night temperature is lower than 8℃ in winter, the growth is slow, the branches become shorter, and the number of double-hearted flowers increases. When the night temperature is lower than 5℃ for a long time, the new branches will be shorter and the number of blind branches will increase. The ideal temperature difference between day and night is 10℃~12℃.
Install a temperature and humidity recorder or a dry and wet thermometer in the greenhouse to observe the temperature changes in the greenhouse, and perform temperature adjustment management according to the temperature changes. When the temperature is high, open the skylight and surrounding side windows for natural ventilation and cooling. When the daytime temperature is higher than 30°C, use shading for cooling.
In hot and dry seasons, spray cooling can be used; when the temperature is low, close the side windows around the greenhouse and add thermal insulation curtains in the greenhouse. The thermal insulation curtains are mainly used to prevent heat exchange and loss at night, increase the temperature of plant leaves and prevent dew. Formation, thereby increasing the yield and improving the quality of cut flowers, especially for red varieties, but the insulation curtain cannot always be completely closed during the day.

Humidity control

The relative humidity required during the budding and leaf growth stages of roses is 70% to 80%, and the relative humidity required during the flowering stage is 40% to 60%. The daytime humidity should be controlled at 40%, and the nighttime humidity should be controlled at 60%. When the humidity in the greenhouse is higher than 90%, water droplets begin to form on the greenhouse film, water tank, plants and leaves, which can easily induce a variety of diseases. Soil moisture conditions are crucial to the growth, development, and yield of roses. Changes in soil moisture conditions must be paid close attention to throughout the rose growing season.
Generally speaking, the weather in northern my country is relatively dry in spring, so germination water, flowering water, flowering water and post-flowering water should be watered in time, about once every 15 to 20 days, to maintain good soil moisture at all times.
In fact, watering and fertilizing are combined during production. As long as it does not rain immediately after each top dressing, watering must be done in time, otherwise the top dressing will not achieve the desired effect. Border irrigation is generally used to water rose gardens, but this method consumes a lot of water and can easily cause a large amount of soil nutrients to be lost. Therefore, the amount of water should be controlled when watering, so that it can irrigate the rhizosphere soil thoroughly.
Narrow border irrigation should be promoted in production, which can save a lot of water. Where conditions permit, drip irrigation should be developed in rose gardens, which can not only save a lot of water, but also maintain soil aeration and prevent soil compaction.

Lighting control

Roses love light, especially diffused light. The light saturation point of the blade is 35000~50000Lux, and the light compensation point is 10000Lux. The synthesis of anthocyanins in cut roses requires ultraviolet light, but too strong ultraviolet light will cause black edges on the petals of red varieties. For red varieties, it is suitable to use a greenhouse film with a transmittance of about 20% in the 0~350nm band.
On cloudy and rainy days, a certain amount of scattered light must be provided. Do not use a shading net during rose budding to ensure that the plants have sufficient light; after budding, you can use a 60% to 75% silver-gray shading net between 10:00 and 16:00 on a sunny day; do not shade on continuous cloudy and rainy days in summer , no shading in winter, no shading when the greenhouse soil surface is too wet, downy mildew, or gray mold is present.

Cultivating and weeding

The rose garden should be plowed and weeded in time after every watering and rain. This can not only loosen the soil, but also prevent weeds from growing and competing with the roses for water and nutrients. Every year when the rainy season comes, the rose garden should be cultivated multiple times to effectively loosen the surface soil, increase soil permeability, improve soil air conditions, ensure normal growth of the root system, and prevent the occurrence of root rot and other diseases.

Rose Pruning Techniques

Plant type culture

In the seedling stage, remove all flower heads when they are about the size of peas and keep the leaves. When the length of the branches is more than 50cm, press down the branches. Be careful not to break the branches. The newly sprouted thick branches are used as cut flower branches, and the thin branches are pressed as vegetative branches; the thin branches sprouted from the vegetative branches continue to be pressed.
When pressing branches, be careful not to cross each other between plants or branches. The number of branches should be enough to cover the sides of the border so that the leaves can get sufficient light. Layering should generally be performed in the afternoon on a sunny day. When pruning vegetative branches, remove thin branches and short branches within 10cm of the roots to increase the light in the lower parts and promote their germination.

Pruning during flowering period

The pruning principle is to leave low piles in spring and summer and high piles in autumn and winter. If the diameter of the lower part of the branch is about 0.5 cm, 2 to 3 bud eyes will be retained; if the diameter of the lower part of the branch is about 0.8 cm, 3 to 5 bud eyes will be left; for flowers less than 50 cm in length or blind flowers or deformed flowers with a diameter of 0.5 cm The above branches should be cut off in time; branches with a diameter of less than 0 or 5cm and a higher germination position should be pruned. The main branches can be cut by pile shears or retraction pruning. Branches with a low germination position can be directly pressed into vegetative branches. The general principle is to lift thick branches upward and push down thin branches.

Rose finishing techniques

Pruning refers to cutting off all the branches of the rose from the base, and pruning refers to cutting off a small part of the branches. In order to promote the vigorous growth of rose bushes, bright flower colors and high oil production rate, proper pruning and pruning must be carried out. Corrugated roses are upright and clustered, with strong germination ability. When pruning, attention should be paid to ventilation and light transmission. The strips should be evenly distributed and kept at a certain distance to prevent the wind from rubbing the branches against each other and damaging the flower heads.
After the flower bushes are pruned, harvesting flowers and field management operations can be facilitated. For newly planted one- to two-year-old rose bushes, after pruning, the branches and leaves must grow well and bloom early. Rose garden flowers that are more than three years old have a high yield and need to be pruned in time to prevent premature aging and yield reduction. To prune roses well, you must understand the reaction after pruning.
Different varieties of roses, different cultivation and management levels, and differences in soil and fertilizers have different reactions after pruning. Pruning should make the rose strips thicker, with the buds in the upper part having better quality than the buds at the base, germinating earlier and growing vigorously. When pruning the whole school, you must understand the variety characteristics and growth habits of roses, and master the principles of pruning. When pruning, control the upward growth of thick branches, and cut off the top tips at appropriate positions to promote the growth of roses, inhibit the rise of flowering parts, and avoid the occurrence of empty and bare lower parts of the branches.
Proper pruning twice in summer and winter can make the branches ventilated and transparent, enhance the light, and concentrate nutrients on the flowering branches. For rose bushes with particularly strong branches and leaves, you may not necessarily harvest many flowers, because most of the nutrients are consumed in vegetative growth. On the contrary, if the shrub blooms too much and consumes too much nutrients, it will easily cause the shrub to weaken and seriously affect the flower yield in the coming year.

Pruning of roses

The principle of pruning roses is: if the flower clusters are planted in a bead-shaped planting method, 15 to 20 thick branches can be left in each cluster; if they are planted in a hedge-shaped planting method, a certain distance should be kept between the branches, and cross branches and dense branches should be kept. Prune off branches, overlapping branches, slender branches, lodging branches, dead branches and branches infected by diseases and insect pests, so that nutrients can be concentrated on the flowering branches, so that the flowering branches can grow strong.
Pruning should be based on specific conditions, mainly light pruning, and remove unnecessary branches. If too many branches are pruned at one time, it will be detrimental to the production and storage of nutrients, destroy the balance between the above-ground parts (branches) and underground parts (roots), and affect the growth of flower branches and the yield of flowers in the coming year. Fertilizer and water management must be strengthened after pruning, otherwise the new shoots will sprout.

The pruning method is as follows:

①One-time update method.

Before and after frost, cut off all the branches of the roses 5 to 6 cm above the ground, then cover the remaining branches with fine soil and cultivate them into a steamed bun shape. In the spring of the second year, many new branches will grow from the roots of the rose. After the new shoots stop growing, cut off the overly dense and thin branches. The remaining branches should be evenly distributed, ventilated and light, and fertilizer and water management should be strengthened. In the spring of three years, roses grew vigorously and flowers were harvested.

②Second update method.

Cut off half of the aging branches of the flower bush and use the remaining branches to produce flowers. Wait until the roses bloom and harvest and then renew the remaining branches. This will not reduce the flower yield due to pruning the branches.

③ Update the law year by year.

This method is commonly used in various places to prune roses. Every year, according to the growth conditions of the rose bushes, we should promptly cut off dead branches, slender branches, aging branches, and branches infected by diseases and insect pests, so as to promote the growth of new branches every year, maintain the strong growth of the rose bushes, and achieve the purpose of renewal and rejuvenation.

【Precautions】

①For grafted rose seedlings, all branches on the rootstock must be cut off. The pruning branches should be distributed reasonably and not to one side. The old branches should be appropriately cut off to renew and rejuvenate in a timely manner. Prune annual branches to retain outward-facing buds and encourage lateral branches to form a large number of flowers. Leave 1 to 1.5 cm of stumps above the outward-facing buds to prevent the branches from drying downward and affecting the growth of buds under the cutting edge.
② When pruning, cut the upright and thick leggy branches at a height of 80 cm from the ground to encourage them to form lateral flowering branches. Do not prune too late, otherwise the branches will not sprout and grow. Aging branches should be cut off 5 to 6 centimeters above the ground to allow new branches to sprout. When pruning, select the full buds on the strips to cultivate strong branches.
③Pruning should be done after the roses are harvested. Because the period from the end of flower collection to the time when roses go dormant and fall leaves is the growth and development period of roses, which require a lot of nutrients. If they are allowed to grow naturally, it will increase nutrient consumption, which will be detrimental to the growth of flowering branches in the coming year and affect flower yield.
④ The cutting edge of pruning tools should be kept sharp, and the cutting edge should be smooth and neat to avoid tearing the cutting edge and affecting germination and growth. According to relevant experiments, there are many advantages to pruning roses. Take the six-year-old rose bushes planted in the shape of beads as an example. Under the same management conditions, the pruned rose bushes have thick and evenly distributed strips, are ventilated and light-transmissive, grow vigorously, have large leaves, are green in color, and have large branches with many flowers. , high oil yield, 300 to 400 kilograms of flowers per acre. Unpruned bushes are prone to decay, with densely crossed branches, poor light transmission and ventilation, many slender branches, small leaves, yellow color, small flowers, few flowers, poor quality, low oil yield, and the breeding of diseases and insect pests every day. The yield of flowers per mu is only 15 to 40 kilograms.

Pest and disease control

During the production process of roses, the prevention and control of diseases and insect pests adopts the prevention and control principle of “prevention first, comprehensive control”. Once diseases and insect pests occur, the quality of cut flowers will be reduced and economic benefits will be affected. Regularly check the isolation measures of the greenhouse to control the invasion of pests; clean the greenhouse film in time, and ventilate and remove moisture in time as the temperature and humidity change. When watering and fertilizing, do not splash water or fertilizer on the leaves, and avoid using water by pouring.
Remove weeds inside and outside the shed in a timely manner to prevent pests from overwintering. Remove susceptible plants and diseased leaves in a timely manner, and treat them with chemicals to control further spread of the disease. After each flower picking, the plants should be sprayed with protective chemicals to prevent diseases from invading through wounds.
When using chemical pesticides for control, fumigation (sulfur fumigation, chlorothalonil compound fumigation) should be used as much as possible. When using spray methods, pesticides that are not easy to leave stains should also be used, such as suspension agents, aqueous agents, emulsifiable concentrates and other formulations of pesticides. Pesticides and fungicides.

Cut flower harvesting of roses

Cut flower roses can be harvested from 7:30 to 10:30 in the morning and after 16:30 in the afternoon. Before picking flowers, the flower picking bucket must be cleaned before adding preservative liquid and placed in the harvesting shed to ensure that the cut flowers are inserted into the preservative liquid within 5 minutes after picking. The cut flowers must be transported to the cold storage for pre-cooling as soon as possible. The cold storage temperature is 5±1 ℃. Harvesting standards must be determined based on cut flower varieties, market entry, transportation distance and time, etc. Flowering index:
1. The sepals are slightly loose and the tops of the petals are tightly hugged, suitable for long-distance transportation and storage.
2. The calyx is loose and suitable for long-distance transportation.
3. The petals extend out of the sepals, which can be used for both long-distance and short-distance transportation.
4. The outer petals begin to loosen, which is suitable for short-distance transportation and nearby wholesale sales. In addition, the harvesting standards can be adjusted appropriately according to the characteristics of the variety and the harvesting season. Early harvesting is appropriate when the temperature is high in summer, and the harvesting maturity is greater when the temperature is low in winter. Harvesting too early or too late will affect the vase quality of cut flowers.