How to grow Chinese roses? Detailed guide to cultivation methods and precautions

In China, Chinese roses (Rosa chinensis) are a fairly popular ornamental flowering plant. Their blooms are very vivid, and the colors are especially varied. Common flower colors include red, white, yellow, and also pink. In recent years, some new cultivars even produce bicolored Chinese rose flowers.

The Chinese rose is a flower that many gardening enthusiasts love to grow, and it is also fairly common in everyday life. They always bloom quietly, bringing growers a great deal of delight. Compared with the delicate rose and the aloof narcissus, the Chinese rose can be said to be very straightforward. When they bloom, they do so boldly and generously, with fragrance filling the air, and people feel especially happy when they see them.

These days there are a great many friends who love Chinese roses, and many of them plant a few on their own balconies. However, in order to grow potted Chinese roses well, friends still need to understand some care techniques; only in this way can they grow Chinese roses successfully.

Cultivation methods for Chinese roses:

1. Chinese roses very much like to grow in an environment with ample light and good ventilation. When caring for them, friends can place them on a south-facing balcony, which not only provides good light conditions but also good ventilation. However, friends must not let Chinese roses be directly exposed to scorching sun, otherwise their flowers will easily dry up.

2. Chinese roses like to live in a relatively humid environment, and friends need to keep the air humidity above 75 percent. When the air becomes relatively dry, friends need to spray some clean water on the leaves and around the plant, which can raise the air humidity.

3. In spring, Chinese roses grow very rapidly, and friends need to prune them in time. Every year in May the Chinese roses will bloom, and after the flowers fade, friends should cut off the spent flowers and also prune the branches appropriately. This is done so that when the Chinese rose blooms the second time, the flowers will be larger and even more beautiful.

4. Watering Chinese roses is also something friends need to pay special attention to. This plant has relatively strict water requirements; it likes to grow in moist soil, but it must not be overly wet, otherwise there is a risk of root rot. Nor should the plant be grown in soil that is too dry, otherwise the roots of the Chinese rose will easily wither. Therefore, during the growing season, friends need to replenish water frequently for Chinese roses so as not to affect the plant's growth.

When caring for Chinese roses, the key focus should be on the prevention and treatment of diseases

There are mainly the following ways to prevent its diseases:

(1) Fungal infection:

Black spot: It mainly attacks leaves, petioles and young shoots. When the leaves first become affected, small purple-brown to brown spots appear on the upper surface, and after they expand they are mostly round or irregular dark brown lesions. You can spray carbendazim, thiophanate-methyl, daconil and other such chemicals.

Powdery mildew: It attacks young leaves, with white powdery material appearing on both sides. Early symptoms are not obvious. About 3 to 5 days after the white powdery layer appears, the leaves become water-soaked in appearance, gradually lose green color and turn yellow, and in severe cases cause the leaves to drop. Spraying carbendazim or triadimefon at the onset of the disease is enough, but Guoguang Yingna has the best effect.

Leaf blight: It mostly invades from leaf tips or leaf margins, starting as small yellow spots, then rapidly spreading inward to form irregular large lesions. On severely affected leaves, as much as 2/3 of the leaf dries up, and the diseased area loses green color, turns yellow, becomes brown, dries and drops off. To prevent and control the above diseases, in addition to strengthening fertilizer and water management, in winter you should cut off diseased branches and leaves, clear away fallen leaves on the ground, and reduce the sources of initial infection. When disease occurs, integrated control should be adopted, and fungicides such as carbendazim and thiophanate-methyl should be sprayed.

Cultivation methods and precautions for Chinese roses

Many beginners growing Chinese roses are looking up the cultivation methods and precautions for Chinese roses, hoping to find a way to grow them from this article. Although this article cannot be called a perfect article suitable for beginner growers, it includes the selection of Chinese rose cultivars, key points of daily care, and the prevention and treatment of pests and diseases, and is very much worth growers' attention.

I. Cultivar selection

First, you have to choose the cultivar you want. There is no such thing as a good or bad cultivar, only one that suits you. Every Chinese rose, once bred, always has its merits and always has a reason to exist. Do not blindly follow trends, and do not be an image-chaser. Choose the cultivar you need most and that suits you best according to your growing environment. Do not switch to another new cultivar before this one has even shown results; in the end, not a single one will look good, and new cultivars are updated too quickly. Some cultivars need to reach maturity to produce astonishing blooming results. Perhaps you are not satisfied with them as young plants, but once they take shape they will delight you immensely. Note: do not blindly pursue new cultivars.

Balcony growers: Choose those cultivars with a large flower quantity, multiple blooming seasons, and a not-too-large plant spread. Be sure to check the information first, otherwise before you even see flowers they will turn into trees. In fact, the flowering performance in many materials translated from foreign languages is very inaccurate, since the climate is different; you should refer to the experiences of people who have grown them. You can choose some small-spread Austin roses, floribunda roses, miniature roses, etc. It is not that only miniature roses can be grown on a balcony; some small-spread ones are also fine, for example Misaki, Austin's Juliet, Miranda and others are quite suitable.

Terrace: Similar to a balcony, but you can choose some shrub types, use flower stands and flower pillars to grow small climbers, and also plant a few HT roses, but classical roses and grandiflora roses are not recommended.

Courtyard: Choose your cultivars according to the actual situation in the yard. If there is a wall, then set up a climbing type; if there is a flower stand, set up a small climber; if there is an arch, set up a climber. If the wall is large, then mix once-blooming and repeat-blooming types. Some once-blooming old roses are truly beautiful, always able to give you a big surprise, and they are easy to grow and easy to care for. Combine them according to the colors you like. In open areas, plant a few grandifloras; in clusters they look very nice. Along the edges you can densely plant some HT types. Beside rockeries and in corners you can plant a few old roses, which have a strong fragrance and a large flower quantity, and are very spectacular. To make a true rose garden, you cannot do without these old roses. Although they bloom only once, when they do it is very spectacular and enough to delight you for a whole year.

Specific usage recommendations:

Arch: Most people, when they mention an arch, think of climbing Chinese roses, but in fact climbers are not suitable, because climbers grow very tall and grow endlessly, crushing the arch, as happened with my own. Moreover, the lower part of climbers does not easily bloom, and many climbers do not flower well, and few are fragrant. So the most recommended are the small climbers of the Austin type, such as Morris, Wildwood, Margaret Princess, Claire Austin, Tess, Gertrude Jekyll, Teasing Georgia and so on.

Wall: It is divided into the general fence type and the high wall type. For fences the same height as an arch, use the same approach. For a high wall, choose climbers. If the wall is long, you can match several colors together, and combine repeat-blooming with once-blooming types.

Trellis: If it is just around a pillar or the like, the same as for an arch. If it needs to cover an entire pergola, you can choose large climbers; Eden Rose, Alchymist and this type are very suitable.

Flower bed: Just choose low-growing cultivars. As for the cultivars, the ones I mentioned above for the balcony will do. Generally a flower bed is always together with a fence and a wall. In the flower bed plant these low-growing ones, and above them choose large shrubs.

Potted plants: Choose some cultivars with vigorous growth and lateral spreading, such as Austin's small shrub types, floribunda roses, and miniature roses.

Cultivar enthusiasts: Then it is hard to say, haha, everyone has different preferences, choose for yourself!

Collectors: Collect every cultivar, as long as you have the space, haha.

II. Purchasing and handling plants

Domestic production started late and the level still cannot match foreign levels. European roses generally mostly come only as small plants of about half a year old. Those large root-grafted plants still need some time, but this is the trend and a must. Note that I mean own-root grafted ones, like the ginseng-like roots of imported bare-root plants that everyone has seen. Grafting onto a cutting rootstock cane does not belong to this category; that type ages quickly, and once the rootstock sprouts, you will have plenty of trouble.

I first want to emphasize what kind of plant is a strong plant. It is not that a taller plant is a strong plant, so I do not like it when people ask me how tall your plant is. Vigorous roots and fresh leaves are more important than anything. If the roots are good, then after receiving it there is no need for acclimatization; it grows directly, much faster than a slightly larger bare-root plant. If the roots are not good, then during the period when new roots are regrowing, if it does not hold on, it dies. Leaves are also very important. Part of the root's water uptake depends on root hairs, which provide the driving force for water uptake according to concentration differences. This is the principle behind strong fertilizer burning roots: when the fertilizer is too concentrated, the external concentration is high, and water from inside the roots is drawn out. Another part depends on the leaves; evaporation from the leaves provides the driving force for the roots to absorb water. If there are no leaves and the roots are also poor, water cannot be taken in and the plant dies of dryness, and no matter how much water you pour, it is useless. This is the principle behind many plants bought in autumn that have few leaves and then die. Also, in summer you absolutely must not prune until only canes remain. Many people, seeing disease, prune all the leaves away, and in the end even prune the plant to death. So I hope growers will not ask me again how tall the plant is; it is really hard to answer. Tall is not necessarily good. If you want height, without pruning it can quickly grow to one meter, but there is no need for that; you should look at the overall condition. It is fine as long as the plant is healthy, and small is not a problem.

Regarding acclimatization after receiving the plant: if the roots are very good as described above, with many white new roots present, then no acclimatization is needed. In spring or autumn you can directly plant it in the ground or repot it and then place it in the sun. In summer, plant it in the evening, then water thoroughly. If the sun is not especially strong, it can get sun the next day. If it is really large, place it in a shaded spot for a few days and that is enough. Pay attention to ventilation and diffused light. Note: absolutely, absolutely do not acclimatize it indoors, because after a week, once it is exposed to the sun, it will certainly die. If the root ball is very hard and no new roots can be seen on the outside, you can peel off a layer of soil slightly so the roots contact the new medium, which helps rooting. If you are using a peat-type medium, there is no need for this; just plant it directly, and there is no need to worry about nematode problems.

III. Medium

Although Chinese roses do not have high requirements for the medium and basically can be grown well in almost anything, a good medium makes it easier to grow good plants and can reduce the input into care. The most reasonable ratio for a potting medium is 30 percent solids, 35 percent air, and 35 percent water. Although it is impossible to follow this strictly, you can use it as a guide when choosing various media to mix. For soil, the ratio of solids, air, and water is 50 percent, 25 percent, and 25 percent respectively. Mediums are a big topic; if you start discussing it, you could compile a book, and there are many kinds of mixes. Roughly, just make your own mix according to the materials available around you; as long as it is loose and breathable, it is fine. Common formulas include: garden soil : coarse sand = 6:4, peat : perlite = 6:4, peat : pine bark = 6:4. It is not very strict, and you can follow your own approach. If you mix in some organic fertilizer, even better. Organic fertilizer can be slowly decomposed by microorganisms to release nutrients, can strengthen the granular structure of the soil, make the soil loose, and give good aeration and drainage, so it will not become very compacted. It is recommended that pots with garden soil had best add some organic fertilizer. There is also a misunderstanding to understand: base fertilizer is not fertilizer placed at the bottom of the pot, because that way the fertilizer easily flows away with water. It can be mixed into the soil, or applied in a ring in the surface soil around the roots; roots have a tendency to grow toward fertilizer. There is also a common fact that many people do not believe: potted plants grow better than ground-planted ones. You do not believe it, huh.

IV. Pot selection

Generally a half-year-old small plant can be transplanted into a pot about 16 cm in diameter. Do not change to a very large one all at once just for convenience; if the water is not easy to control, the roots will rot. Then after growing for another half a year or so, change to a larger pot, increasing the pot size by 10 cm each time.

V. Planting

When planting, support the surface of the pot with your palm, then turn it upside down, and the nursery pot can simply be removed. Then turn it upright and place it into the pot or planting hole. Absolutely do not pull it out directly. Be careful to disturb the root ball as little as possible, as this will damage the root system. A slight squeeze can break many root hairs, because they are too fine. You know the importance of root hairs, right. After planting, water promptly and thoroughly. Even if it rains, be sure to water again. Watering allows the root hairs to cling to the medium and directly absorb water; otherwise water absorption will be affected. There is one more point: in winter some growers worry that after watering it will freeze, but in fact having water there also provides a buffering effect; without water, the roots are more likely to freeze. So remember firmly to water promptly after planting, and do not delay until the next day. If you do not water, what will its roots do that night?

Many growers report that after planting, the leaves turn yellow and then drop. In fact, this is caused by water shortage at some point. After water shortage, in order to reduce water evaporation, the plant produces abscisic acid, and the leaves drop, as if entering dormancy. Although it will not necessarily cause death, it will affect growth. Many bare-root plants are also like this.

VI. Fertilization

First understand what plants need. What they need most is nitrogen, phosphorus, and potassium, plus trace elements. So as long as these are supplied, the plant has enough. Organic fertilizer also uses these, only releasing them relatively slowly, which can ensure long-term nutrient supply for the plant and also promote looseness and so on. Chicken manure and bone meal are the main sources of phosphorus fertilizer, but their fertilizer effect is very slow. Phosphorus promotes flowering, so it is very beneficial to Chinese roses. Plant ash is the main source of potassium fertilizer and promotes sturdy branches. Bean cake contains a large amount of nitrogen fertilizer and phosphorus fertilizer.

So these chemical fertilizers can all meet the need. Chinese roses are not something you eat, so a little chemical fertilizer is no problem. The simplest and most convenient is to use controlled-release fertilizer. Controlled-release fertilizer is formulated according to the plant's needs and is used once a year, very convenient. The release rate of controlled-release fertilizer varies according to the amount of water and the temperature, so there is no need to worry about winter and such. If there is no controlled-release fertilizer, you can usually spray foliar fertilizer or water it in. Dilute water-soluble fertilizer basically at 1:1000, once a week, to keep the plant healthy and very vigorous. However, different ratios of nitrogen, phosphorus, and potassium are used at different seedling stages. For small plants and in autumn, use a bit more high-potassium; when flowering, use high-phosphorus; to grow leaves, use a bit more nitrogen. But for simplicity, using a general-purpose one is usually fine.

I personally also want to emphasize one point: many sayings circulate that you should not fertilize when growing small plants, but that is under the premise of bare roots or a medium containing a small amount of fertilizer, such as with added organic fertilizer. If you are using new nutrient soil with no fertilizer added, and the roots are also very good, then you definitely still need to fertilize. It is best to apply light fertilizer frequently; otherwise, with no nutrients for the roots, branches, and leaves, it will not be able to grow all at once.

There is also a misunderstanding that you cannot fertilize in summer. Summer is the fastest growth period of the year for plants. At this time, if you feed it fully, how can it grow fast? Otherwise it may enter dormancy and such. This is also often the reason the flowers bloom small in summer. In summer, the best approach is light fertilizer applied frequently, with plenty of water and plenty of fertilizer. It will grow quickly, and the flowers will still be very large.

VII. Pruning

There is a lot to say about pruning, and I will supplement it properly later. I will discuss it a little here. In fact, it becomes clear just by looking at a diagram.

Just follow this approach, and you will certainly be able to grow a very full ball shape. Many people always say this one easily turns into a tree, that one easily turns into a tree. In fact, its turning into a tree is caused by your indulging it. If you prune it this way from the beginning, the tree form will not appear. With just a few branches still tied straight up, how can it be encouraged to send up basal shoots? It will only know how to grow upward.

However, I want to emphasize a few points about major winter pruning. First, the pruning of each type of Chinese rose is different. Old roses have old rose pruning methods, HT has HT pruning methods, miniature roses have miniature rose methods, and climbers have climber methods. Roughly remember: old roses can be pruned higher, leaving more branches; modern roses can keep just three to five large branches per plant, pruning to about 30 to 45. Small plants bought only half a year ago do not need pruning in winter; leave them to accumulate nutrients. With more leaves, they grow faster and the root system is better, and branches and leaves are proportional to the root system. This way, basal shoots are easy to produce in spring, and they basically will not drop leaves in winter. Wait until the basal shoots emerge before pruning.

VIII. How to promote basal shoot production

If you want to produce a thick and strong basal shoot, you can do two things. First, nutrition must keep up; the plant must be very robust with sufficient fertility. Second, break apical dominance; you can bend the branches sideways or pull them horizontal. Although pruning can also destroy apical dominance, pruning affects the plant's nutrient uptake, so retain as many leaves as possible. This way you will certainly get a very strong basal shoot. Then, if the original branches are very thin and weak, you can cut them off. Also note one point: do not do this too late, otherwise when the shoots emerge and winter comes and they freeze, that will not be good.

IX. Pests and diseases

For pests, generally as soon as you see them slightly, you need to apply pesticide. The main ones are red spider mites and caterpillars.

Red spider mite: Everyone should recognize it. As soon as you see it, apply pesticide immediately. If there are not many plants, and you can pinch them off with your hand, then pinch them off. If not, wash them with water. Take a spray bottle and spray them every day; after spraying for three days they will be washed away. But you must spray the undersides of the leaves. If there are many Chinese roses and many pests, then you can only apply pesticide. Generally you can use abamectin and pyridaben, which is the most used. If this does not work, you can switch to a new pesticide. It may be a bit expensive, but the effect is very good.

Caterpillars: If there are not many, pinch them off. If there are many, biological pesticides are recommended, Bacillus-type ones. The efficacy lasts one month, and they are non-toxic to people. This is the best.

Aphids: Generally a little imidacloprid can deal with them.

Diseases: Mainly black spot and powdery mildew. This depends mainly on prevention. Basically at home, spray alternately once every one week to half a month, and after each rain, spray once more as a supplement.

Black spot: Black spots will appear on the leaves, with yellowing around them. In severe cases, the leaves of the whole plant will turn yellow and drop, causing a great impact.

Powdery mildew: White powder will appear on the leaves, and then the leaves will curl. This occurs very readily in both spring and autumn. It generally relies on usual prevention, and once it appears it is also very troublesome. It mainly appears on young leaves, and once present, cutting them off directly is the most convenient. However, there are several chemicals that are very effective. After spraying for three days, the powdery mildew is finished.

Powdery mildew: after spraying fungicide, the powdery mildew was killed

10. Common problems

Black stem: It is mainly caused by weak plants and poor roots. This is a problem of the plant itself, and applying chemicals has little effect. The recommendation is more ventilation and keeping the medium on the dry side.

Yellow leaves: One case is that the old leaves at the bottom turn yellow just after receiving the plant. This is premature aging caused by shipping and is not a big problem. Roots and leaves are proportional; if the roots are slightly damaged, leaves need to be reduced to balance it.

Another case is that leaves turn yellow during normal times, mainly caused by inadvertent drying. Perhaps you watered thoroughly in the morning, but at noon it still wilts from water shortage. Although it recovers by evening and you think it is fine, damage has already occurred. After water shortage, it needs dormancy to reduce losses, and the most direct manifestation is leaf drop. Or it may directly wilt from drying. After this, do not immediately water thoroughly; first spray a little water, water slightly, and after it recovers, then water. Do not follow severe dryness with immediately heavy watering, or the roots will certainly rot.

How to grow Chinese roses, cultivation methods and precautions for Chinese roses

Chinese roses bloom in all four seasons and are commonly used flowers in courtyards and gardens, able to fill seasonal gaps. Many people also grow Chinese roses at home, so how do you grow Chinese roses, and what are the cultivation methods and precautions for Chinese roses?

Chinese roses like sunlight, tolerate cold and drought, and need an environment with good drainage, air circulation, and shelter from wind. They have strong adaptability and do not have high requirements for soil.

Cultivation methods for Chinese roses

Soil: Chinese roses have strong adaptability, and general soil can support growth. A slightly acidic sandy loam rich in organic matter and with good drainage is most suitable.

Temperature: The optimal growth temperature for Chinese roses is 22 to 25°C. In winter, when the temperature is below 5°C, they enter dormancy. When the temperature is below -15°C, cold damage occurs. In summer, when high temperatures persist above 30°C, the quantity and quality of flowering are affected.

Light: Chinese roses like sunlight and need at least 5 to 6 hours of light per day; otherwise the growth of the plant and the quality of flowering are affected. In summer, when temperatures are high, if there are tall buildings and concrete ground around, pay attention to providing appropriate shade and sun protection.

Watering: If the branches and leaves of Chinese roses wilt, replenish water promptly, and note that each watering should be thorough. In addition, during the flowering period of Chinese roses, make sure there is sufficient water, but it must not be too dry or too wet, otherwise it easily causes flower drop.

Fertilization: Chinese roses do not need a high amount of fertilizer. Appropriate fertilization can be done in winter, spring, or after May during the peak growing season. In winter, apply a little organic fertilizer at the roots of Chinese roses to strengthen their cold resistance for overwintering. In March, before Chinese roses sprout in spring, apply organic fertilizer to supplement nutrients. After May, during the peak growing season, apply a supplementary fertilizer once every 10 days. You can use thoroughly decomposed and fermented fish liquid and vegetable leaf liquid, mixed at a ratio of 3 parts fertilizer to 7 parts water, and apply it. Stop fertilizing by November.

Pruning: Chinese roses generally need pruning of spent flowers and withered leaves beginning in mid-to-late May, which can strengthen plant vigor. When pruning, cut about a fingernail's length above the new buds, which is beneficial to the growth of the Chinese rose plant.

Precautions for Chinese roses

The planting location for Chinese roses must have good air circulation and also be sheltered from wind. When fertilizing Chinese roses, be careful to dilute it; the fertilizer concentration must not be too high, otherwise it easily burns the roots. If you want Chinese roses to produce better flowers, you need to promptly cut off old, weak, and diseased branches to promote the vitality of the Chinese rose, but it must not be too severe, otherwise it easily causes the death of the Chinese rose.

The above are the cultivation methods and precautions for Chinese roses. Special note: when pruning the roots of Chinese roses, do not prune too heavily, otherwise it easily reduces the root's absorption capacity and causes the plant to die.

Further reading:

Chinese rose flower language, how to grow them, cultivation methods and precautions