Daily Care and Flowering Regulation Techniques for Roses in the Zhangzhou Area
How do you care for roses? Today, the Hui Nong Wang editor will walk you through a real-world rose planting and care case from a specific region. Let's learn together about rose care and flowering regulation methods in the Zhangzhou area.
1 Planting and Care
1.1 Planting Time
The Zhangzhou area has a spring-like climate all year round with relatively high air humidity. Roses can be planted in all four seasons, but spring and autumn are the best.
1.2 Planting Density
Rose planting density depends on the variety. Generally, miniature roses are spaced 15cm between plants and rows. Floribunda roses are spaced 35cm x 45cm between rows and plants. Grandiflora roses are spaced 45cm x 60cm between rows and plants. For spreading varieties and climbing roses, the row and plant spacing is about 100cm.
1.3 Planting Methods
In landscaping, roses are mostly planted in blocks according to the designed color scheme. Grandiflora roses are best planted in whole beds to facilitate growth and soil drainage. Generally, the bed width is 70cm, the ditch width is 50cm, and the bed length depends on the length of the planting site, with two rows planted per bed.
1.3 Watering
After the seedlings are planted, water thoroughly the first time, and then water as needed thereafter. For newly planted roses, the leaves can be misted frequently, but not too wet, to help increase air humidity and lower temperature, which helps the plants survive.
Roses are drought-tolerant and afraid of waterlogging. Water management should follow the principle of watering when dry and draining when wet. Drain promptly during heavy rainfall. Water management differs between the growing season and the dormant season. In summer, when soil temperature is high, watering should be done in the morning or after 5 PM, usually once every 2 to 3 days. In spring and autumn, water once every 4 to 5 days, and in winter, water once every 7 days.
1.4 Fertilizing
Roses love fertilizer and need balanced nutrition during growth. The main fertilizing methods are applying base fertilizer before planting and topdressing during the growing season. The amount and method of fertilizing roses vary by growing season. After newly planted seedlings grow new roots for 10 days, a light fertilizer can be applied, mainly a compound fertilizer with equal amounts of nitrogen, phosphorus, and potassium, watered around the base of the seedlings at about a 300-fold dilution. During the growing season, roses need continuous topdressing to replenish the nutrients consumed by continuous flowering. To prevent soil compaction, topdressing can be combined with decomposed organic fertilizer and cake fertilizer, generally applied once every 10 days or so. Regularly, foliar fertilizers such as monopotassium phosphate, urea, Gaomeishi, and ferrous sulfate can also be sprayed on rose leaves. Do not fertilize during the peak flowering period. After the flowering period, along with pruning of branches, a higher-concentration compound fertilizer can be applied at about a 50-fold dilution to promptly replenish the nutrients the plant expended heavily during peak flowering, promoting rhizome division and new shoot formation.
2 Pest and Disease Control
① Black spot disease. Leaves, young leaves, and pedicels can all be affected. In severe cases, diseased leaves become wrinkled and uneven, leaves curl toward the underside, young shoots bend downward or die, and flower buds cannot open normally. Control methods: Check frequently during the disease season, promptly remove and destroy diseased leaves to prevent the disease from spreading. Options include 75% chlorothalonil at 500-fold dilution, 50% carbendazim wettable powder at 500 to 1000-fold dilution, or 80% zineb at 500-fold dilution, sprayed once every 7 to 10 days. To prevent pathogen resistance, chemicals must be used alternately.
② Powdery mildew. It affects rose leaves, young shoots, flower buds, and pedicels. In severe cases, leaves wither and drop. The surface of affected parts is covered with a white powdery layer. Control methods: Prune and shape in a timely manner, remove diseased shoots and leaves, and improve ventilation and light penetration between plants. During the growing season, spray 70% thiophanate-methyl at 1000 to 1500-fold dilution, or 15% triadimefon wettable powder at 1000-fold dilution, both with good control effects.
③ Rust disease. Rust disease affects rose buds, leaves, young branches, petioles, receptacles, and pedicels. Control methods: Promptly remove diseased buds. Options include 50% thiram at 500-fold dilution, or 25% triadimefon wettable powder at 1500-fold dilution.
④ Dieback disease. It mainly affects rose branches and trunks, causing cankerous lesions on the branches and trunks. In severe cases, lesions girdle the stem, and branches below the diseased area shrink and die. Control methods: In autumn and winter, thoroughly prune diseased and dead branches and burn them in a centralized manner. Strengthen cultivation management and apply sufficient base fertilizer. During the growing season, spray 0.1% urea solution to enhance plant vigor. During the dormant period, spray 25% carbendazim wettable powder at 600-fold dilution, or 50% Tuzet wettable powder at 1000-fold dilution, or 50% chlorothalonil wettable powder at 500-fold dilution.
⑤ Aphids. They mainly gather on buds, young leaves, and flower buds to suck sap. When occurring in large numbers, there are honeydew-like black secretions. In open-field cultivation, early spring and early summer are peak periods. Control methods: During the initial hatching period and before egg-laying, spray 40% omethoate at 1000-fold dilution or 80% dichlorvos at 500-fold dilution for control.
⑥ Red spider mites. High temperature and dry seasons favor massive outbreaks. They mainly suck leaf sap. Affected leaves show small yellow spots that gradually spread to the entire leaf, causing leaves to curl, turn yellow, and drop. Control methods: Strengthen cultivation management, clear surrounding weeds and dead branches, and enhance ventilation and light penetration. Remove and burn affected leaves promptly. During pest outbreaks, spray 15% pyridaben emulsifiable concentrate at 2000-fold dilution, or 50% bromopropylate emulsion at 2500-fold dilution, or 40% omethoate at 1000-fold dilution. Since red spider mites have strong resistance, acaricides should be used alternately.
⑦ Scale insects. Their damage is characterized by piercing and sucking sap from tender rose stems and young leaves, causing poor plant growth, mainly triggered by high temperature and high humidity, poor ventilation, and insufficient light. Control methods: When pest density is low, they can be brushed off with a soft brush. During the nymph hatching period, spray 40% omethoate at 1000-fold dilution, or 50% fenitrothion at 1000-fold dilution, or bury granular insecticides such as aldicarb at the roots, using 2 to 3g per plant, for effective control.
3 Flowering Regulation
3.1 Effect of Temperature on Flowering
High temperature and drought can cause roses to enter dormancy or rosette formation, while low temperatures help restore the growth activity of rose plants. In the Zhangzhou area, except for summer, all other seasons are suitable for rose growth. In landscape settings, most roses are planted in the open air, where temperature cannot be manually regulated. Growing in natural conditions, the temperature of each season directly affects the growth status of roses. The author selected several rose varieties in the park, maintained normal water and fertilizer management for the test varieties, and used heavy pruning each time for flower regulation pruning, allowing them to naturally sprout and bloom. Observations and records were kept for one year, recording the flowering and growth conditions of each season.
Experiments show that most roses have strong temperature adaptability. Temperature mainly controls flowering by regulating the flower bud formation period, flower stem elongation period, and rose dormancy period. Temperature is closely related to rose branch growth and development and flower bud differentiation. During the growing season, temperatures in the range of 18°C to 30°C are more suitable for rose growth. Above 30°C, roses enter a dormant state, affecting rose growth. It can also be observed that the time from pruning to flowering in roses shortens linearly as temperature rises. Flower bud development speed increases with rising temperature, so changing the temperature for rose growth and development is a relatively important means of rose flowering regulation.
Flowering prediction and regulation mainly rely on the effective accumulated temperature required for flowering of different varieties. Within the limits of ensuring good fertilizer and water conditions and suitable temperatures, the pruning date of roses is predicted and calculated based on the annual average daily temperature to regulate their flowering date.
Rose flower bud differentiation is mainly influenced by temperature and branch nutritional status. Increased light intensity raises the photosynthetic rate of roses, providing sufficient nutrition for flower development. Light duration affects lateral bud germination as well as the accumulation and transport of assimilates.
3.2 Effect of Plant Hormones on Flowering
In landscaping, temperature and pruning are the main methods for rose flowering control. Plant hormones are generally used less, but plant hormones also affect rose growth and flowering. Plant hormones participate in regulating all aspects of rose growth and development. The relatively high cytokinin content at the base of rose branches indicates that cytokinin is an essential substance for bud germination and growth. Spraying gibberellin on young rose branches can break dormancy, increase the number of flowering branches, and promote flower branch growth. Spraying gibberellin at 50ppm can significantly increase rose length and has an increasing effect on flower stem thickness, leaf number, chlorophyll content, maximum flower diameter, and fresh flower weight, and can improve flower color grade. When the flower buds on new rose branches are about the size of soybeans, if the regulated flowering time needs to be earlier, 10g of B9 can be mixed with 6kg of water and sprayed on the leaves. One spray can delay flowering by 2 to 3 days. In addition, ethephon can be sprayed or poured during the leaf expansion period of roses to extend or promote rose flowering.
3.3 Effect of Pruning on Flowering
In landscaping, pruning timing should be scientifically grasped to control rose flowering and improve the quantity and quality of rose flowers. Pruning should be done in a timely manner to regulate the plant, transferring and concentrating limited nutrients onto retained branches to promote the formation of the next batch of flower buds. To give roses vigorous growth capacity, correct pruning helps maintain tree vigor and plant renewal, and improves flower quality. Pruning should follow the principle of thinning out weak branches and keeping strong ones, and removing horizontal branches while keeping vertical ones.
The time needed from axillary bud differentiation to flower branch budding and flowering in roses is called "days to flower." Generally speaking, the days to flower for most rose varieties is about 35 to 65 days. For the same variety, high temperature, sufficient light, and balanced nutrition shorten the days to flower; lower temperatures, partial shading, and higher phosphorus and potassium content lengthen the days to flower. Understanding this basic rule allows determining the flowering time through artificial pruning regulation based on the required time.
In practical work, flowering regulation of open-field roses mainly relies on pruning because growing temperature cannot be regulated. When regulating rose flowering, in addition to considering the overall growth vigor of the rose plant, the temperature of the pruning season, and the plant variety characteristics, the appropriate pruning position should also be selected based on the development of flower buds to ensure flowering as expected and good quality. In seasons suitable for rose growth, during light pruning, cut at 2 to 5 leaves below the flower. The buds growing on the upper part of the branch are pointed; the flower branches produced are short, budding is early, flowering usually occurs in about 20 days, and the flowers are smaller.
During moderate pruning, cut at the middle part of the branch (6 to 9 leaves below the flower). The buds that grow are round; round buds produce long flower branches, budding takes longer, flowering usually occurs in about 30 days, and the flowers are large.
During heavy pruning, cut at the base of the branch. The buds that grow are flat, bud activity is low, branching is slow, and water sprouts tend to form. Flower branches take even longer to bud, flowering usually occurs in about 40 days, and the flowers are relatively large.
4 Holiday Flowering Regulation Methods
Based on the climate characteristics of each season in Zhangzhou and the characteristics of each rose variety, reasonable pruning of rose plants allows the scenic area to enjoy colorful flowers during every holiday.
New Year's Day and Spring Festival flowering regulation. Roses bloom during New Year's Day and Spring Festival when the growing environment temperature is around 20°C, which is suitable for rose growth.
Most grandiflora roses, if heavily pruned, need about 50 days from new bud germination to flowering. Therefore, around November 10, heavy pruning and branch bending can be carried out on roses. After buds emerge, promptly manage water, fertilizer, pests, and diseases. After New Year's Day, promptly prune spent flowers, and the peak flowering period of roses can extend from New Year's Day to after the Spring Festival.
Floribunda and small-flowered roses can be moderately pruned. It takes about 30 days from new bud germination to flowering, so pruning should be appropriately delayed by about 20 days. After buds emerge, promptly follow up with water, fertilizer, pest, and disease management.
May Day flowering regulation. The growing environment temperature is around 28°C. After the Spring Festival flowering, promptly strengthen fertilizer, water, pest, and disease management.
Grandiflora roses can be treated with a combination of heavy pruning and moderate pruning. Around March 20, cut all spent flowers to the round bud position at the mature middle part of the flower branch. After buds emerge, promptly manage water, fertilizer, pests, and diseases. The peak flowering viewing period is about May 1 to 15.
Floribunda and small-flowered roses can be moderately pruned. It takes about 30 days from new bud germination to flowering, so pruning should be appropriately delayed by about 10 days. After buds emerge, promptly manage water, fertilizer, pests, and diseases.
National Day flowering regulation. June to October is the high-temperature season, and roses enter the summer growing period. To enable roses to bloom well during National Day, try to let them bloom less during normal times, promptly remove buds, water heavily during drought, and frequently mist the leaves to lower leaf surface and ground temperatures and increase air humidity. Light fertilizer can be applied to help them accumulate nutrients and promote robust plant growth.
Grandiflora roses can be treated with a combination of moderate pruning and light pruning. Around August 25, cut off all spent flowers and diseased branches, and cut some flower branches to the round bud position at the mature middle part. Strengthen cooling measures. The peak flowering viewing period is about October 1 to 15.
Floribunda and small-flowered roses can be treated with a combination of moderate pruning and light pruning, with pruning appropriately delayed by about 10 days. After buds emerge, strengthen cooling measures and promptly manage water, fertilizer, pests, and diseases.
4.1 Flower Expo Flowering Regulation
The Zhangzhou Flower Expo is held on November 18 each year. The temperature is relatively suitable for rose growth, but the preceding months have higher temperatures, and roses lack sufficient nutrients. To make roses bloom abundantly during the expo, roses must not bloom during National Day. Strengthen plant care and management in the earlier period and strengthen cooling measures to help them accumulate nutrients and promote robust plant growth.
Grandiflora roses can be treated with a combination of moderate pruning and heavy pruning. Around September 25, heavily prune some thin branches and cut strong flower branches to the round bud position at the mature middle part. The peak flowering viewing period is about November 10 to 30.
For floribunda and small-flowered roses, a combination of moderate pruning and heavy pruning can be used, with pruning appropriately delayed by about 10 days. After buds emerge, strengthen cooling measures and promptly manage fertilizer, water, pests, and diseases.
That is all the content on rose care and flowering regulation in the Zhangzhou area. Everyone is welcome to continue following Hui Nong Wang. There is more exciting content here!
Low-temperature flowering regulation technology was used for the first time to ensure roses bloom abundantly during the Rose Conference
(Original title: "Rose Conference" uses low-temperature flowering regulation technology for the first time)
Tomorrow, the 2016 World Rose Intercontinental Conference will be held in Daxing District, Beijing. A reporter learned from the Beijing Academy of Landscape Science that the academy used low-temperature flowering regulation technology for the first time to ensure roses bloom abundantly during the conference.
In the indoor potted rose exhibition of the "Rose Conference," the academy's shaped roses 'Spectrum,' 'Crimson Fan,' 'Alec's Red,' 'Princesse de Monaco,' and 'Mélangé Lipstick' will participate. According to the normal flowering period, potted roses in the Beijing area bloom by the end of April. To delay the flowering period and make all rose varieties reach peak bloom on May 18, the academy used cold storage for the first time to subject participating varieties to low-temperature treatment, ensuring that during the conference, participants from around the world can see the highest level of self-bred varieties and potted roses of the Beijing Academy of Landscape Science. (WeChat ID: fzwb_52165216)
As the city flower of Beijing, roses are deeply loved by residents for their wide variety, rich colors, and easy care and management. In the self-bred variety park within the conference theme park, Longhe Park, the academy planted six self-bred varieties: 'Red May,' 'Spring Tide,' 'Pearl of the Orient,' 'Pink Flower Carpet,' 'Snow Child,' and 'Cute Ice Cream.' Currently, all plants are growing uniformly and robustly, with buds ready to open, and will reach their best ornamental effect during the conference.
At present, the environmental improvement work in the core area and expansion area of the Rose Conference has been fully completed, with a total of more than 2.17 million rose plants of various types planted, more than 432,000 trees planted, more than 3.669 million shrubs planted, and 262,000 sq m of lawn and ground cover.
In addition, to improve the surrounding environment of the venue, since the beginning of this year, Daxing District has carried out the demolition of various buildings of about 96,000 sq m, road hardening of about 128,000 sq m, exterior facade and wall painting of about 71,000 sq m, standardized rectification of 790 advertising signs, standardization of 76 bus stop signs, and renewal and installation of 570 litter bins. (WeChat ID: fzwb_52165216) The landscape arrangement work around the venue has also been fully put in place, including the installation of 14 groups of three-dimensional flower beds, 3,564 groups of bridge hanging flowers, 1,228 groups of ground-placed containers, 9 groups of node feature displays, 308 groups of flower balls hung on key road lamp posts, 3,600 groups of hanging flowers on the central isolation belt of the central axis road, and 40 rose flower columns.
Rose Conference Author: Geng Xueqing
Source: Legal Evening News
Responsible Editor: Wang Xiaoyi_NE0011
How to Control the Flowering Period When Planting Roses at the Beginning of the Month
There are many rose varieties, and the flowering intervals differ among them, but most intervals are 40 to 50 days long. The higher up, the shorter the interval. The best method is, in daily care, based on variety habits, to observe the flowering interval and pruning position, which can ensure flower supply on time. But conventionally, pruning about 35 days in advance basically ensures flowering on time. Dwarf types, small-flowered types, and single-petaled types have short flowering intervals and bloom almost every month. When old flowers are about to fade, new flowers open. They can be maintained conventionally and will bloom on time even without pruning.