How to fertilize potted roses when they do not bloom, to extend the flowering period

Roses are known as the “queen of flowers”, with brilliant colors, a long flowering period, and a far-reaching fragrance, representing a spirit of unyielding resilience. However, many roses grown in courtyards fail to fully tap into the rose's potential for a long flowering period. To extend the rose's flowering period, the goal is actually to increase the number of times the same plant blooms in a year, which requires meeting higher care standards in growing medium, fertilization, pruning, and pest and disease control.

Many rose beginners do not know that roses bloom in autumn. Generally speaking, most roses bloom in multiple seasons. After the high-temperature period of summer, roses enter a peak flowering period in autumn, usually blooming in early to mid-October (climate varies from place to place, so there is a time difference). You need to seize the opportunity created by the changing climate conditions to develop flowering branches.

Theoretical calculation of the total number of branches and flowers for a normal potted rose (floribunda rose, shrub rose):

Cultivate 5 first-level main branches (including basal shoots), with 3 second-level branches on each main branch and 2 third-level branches on each second-level branch. If all third-level branches can bloom at the same time, the number of flowers on third-level branches is 30. Note: only the main buds are counted, not the multiple secondary buds; it is very difficult for open-air potted roses to achieve such a sufficient and precise number of flowers.

1. Insist on changing the potting soil every year. Take advantage of the rose's winter and spring dormancy and the early stage of new bud sprouting to change the potting soil, replenish it with fresh nutrient soil, and keep the potting soil loose. When changing the potting soil, remove weeds, cut off residual roots, and loosen and arrange the root system so that it produces more new roots.

2. Improve the fertilizer supply capacity. When changing the potting soil, apply a certain amount of decomposed organic fertilizer at the bottom of the pot; during the peak growing period of roses, apply a thin liquid of decomposed cake fertilizer once every 10-15 days. After each flowering, apply a nitrogen, phosphorus, and potassium compound fertilizer once; for those that bloom little or not at all, apply additional quick-acting phosphate fertilizer; after the beginning of autumn, apply only phosphorus and potassium fertilizer, not nitrogen fertilizer; during the dog days and winter, do not fertilize or fertilize less.

3. Pay attention to regulating temperature and light. Roses originally like warmth and light, but in the high-temperature season, potted roses should be moved to a cool place, or grass should be covered over the potting soil to lower the temperature. At the same time, water frequently; in summer, water twice a day.

4. Prune branches frequently. After a rose blooms, it should be cut below the third compound leaf beneath the flower to promote the growth of sturdy new branches and the early appearance of buds and flowers. Key pruning techniques: prune weak and short branches first, and prune high; prune vigorous branches later, and prune short, in order to promote the weak and suppress the strong, and encourage them to bloom uniformly. The pruning length of long branches should not exceed 1/2, to avoid delayed sprouting of axillary buds.

5. Eliminate pests. In spring, roses are prone to aphids, which can be eliminated within half a day by spraying water soaked with cigarette butts or diluted trichlorfon; in summer, they are prone to black spot disease and powdery mildew, both caused by excessive humidity and stuffiness. For mild cases, some diseased leaves can be picked off; for severe cases, spray Bordeaux mixture or thiophanate, sterilizing agent, etc. 2-3 times at intervals of about 10 days for prevention and control.