Why does a tree rose (standard rose) bloom little?

A tree rose refers to a single-stem, tree-like arbor form of rose produced through artificial horticultural techniques, giving it a trunk and a crown, and it retains the rose's characteristic of blooming profusely. However, after many tree roses are planted, they not only fail to retain the rose's profuse-blooming characteristic, but may even fail to bloom at all. Based on years of observation, study and exploration of tree roses, the author summarizes the reasons as follows.

1. Insufficient light and poor ventilation

As everyone knows, the rose is a strong sun-loving flower, and tree roses are no exception. If the plant receives insufficient light, poor ventilation or excessive shading, the branches of the tree rose will become slender and elongated, the leaves will become thinner, and nutrient accumulation will be poor, ultimately leading to poor plant growth, few and small flowers, dull flower color, a shorter flowering period, and so on.

2. Insufficient or imbalanced nutrition

Because the tree rose has the characteristic of blooming multiple times a year, its nutritional requirements are relatively higher than those of other flowers. Throughout the entire growing season of the tree rose, additional fertilizer should be applied several times as appropriate, that is, apply fertilizer once after each blooming of the tree rose so that the rose plant can recover its growth vigor as quickly as possible. When topdressing, pay attention to the ratio of nitrogen, phosphorus and potassium; you cannot apply only a single nitrogen fertilizer or only phosphorus and potassium fertilizers, otherwise it will cause symptoms such as the plant growing only branches and leaves or failing to form flower buds normally.

3. Lack of reasonable pruning

Because the flowering habit of the rose is to form flower buds at the tips of one-year-old branches, pruning should use heading back to increase the number of branches. But more branches are not necessarily better; while appropriately increasing the number of branches, the plant's ventilation and light penetration should be well adjusted. In this way, the plant can be prompted to shift into the reproductive growth stage in a timely manner, and the occurrence of pests and diseases can also be appropriately reduced. During the flowering and growing season, light pruning is generally carried out, and in winter, renewal pruning by cutting back is done. The suckers on the roots and main trunk of the tree rose plant must be removed at any time, otherwise they will consume a considerable amount of extra nutrients, ultimately weakening the plant's growth vigor and affecting bud formation and flowering.

4. Damage from pests and diseases

Due to the invasion of pests and diseases, the branches and leaves of the tree rose plant are damaged, and the effective leaf area for photosynthesis is reduced, thus weakening the overall tree vigor. The main diseases include powdery mildew, black spot, and so on; generally, spraying with 50% carbendazim at 800 times dilution or 70% thiophanate-methyl at 600 times dilution is used for control. The main pests include the rose sawfly (Arge pagana), the rose long-tube aphid (Macrosiphum rosae), and the larvae of the tobacco cutworm (Spodoptera litura), and so on; 48% chlorpyrifos at 1000 times dilution or 90% trichlorfon crystal at 1000 times dilution can be used for control.

5. Variety characteristics

How much a tree rose blooms is also determined by the characteristics of the variety, so varieties that bloom more should be chosen as far as possible; for example, if the crown is a floribunda rose variety, it is likely to bloom more.

6. Late-stage incompatibility

Generally, tree roses are produced by grafting. Therefore, there is a certain difference between the scion and the rootstock, especially for varieties with late-stage graft incompatibility, whose growth state is poorer, ultimately affecting the plant's flowering; some do not bloom, and some even gradually die. Therefore, compatible varieties should be chosen for cultivation as far as possible.

In short, as long as the above problems are adjusted and solved, the tree rose will certainly grow better and better, and will certainly bloom more and more.