How to Grow Potted Chrysanthemums Well? A Detailed Guide to the Latest Care Methods

The chrysanthemum ranks third among China's top ten famous flowers and is one of the Four Gentlemen of Flowers (plum blossom, orchid, bamboo, chrysanthemum). Also known as Shouke, Jinying, Huanghua and so on, it is a perennial herbaceous plant with persistent roots of the genus Chrysanthemum in the family Asteraceae. By cultivation form, it is divided into spray chrysanthemums, single-stem chrysanthemums, large standard chrysanthemums, cliff chrysanthemums, artistic chrysanthemums, desk chrysanthemums and other types. Now let's take a look at how to grow potted chrysanthemums well!

Growth Habits of Chrysanthemums

The chrysanthemum is a short-day plant and can bloom earlier under short-day conditions. It likes sunlight and dislikes shade, is fairly drought-tolerant, and fears waterlogging. It likes a warm and humid climate but can also tolerate cold, and in the depths of winter its rhizomes can overwinter underground. The flowers can withstand light frost, but the seedling growth and branching bud-setting stages require relatively high temperatures. The optimal growth temperature is 18-21℃, with a maximum of 32℃ and a minimum of 10℃. The underground rhizomes generally tolerate a low-temperature limit of -10℃. The minimum night temperature during the flowering period is 17℃, and during the flowering period (middle and late) it can drop to 15-13℃.

Propagation Methods for Chrysanthemums

1. Shoot cuttings: In autumn and winter, cut off the outer basal shoots of the plant and insert them into a flower pot or a coarse sand cutting bed inside a greenhouse or plastic tunnel, maintaining a room temperature of 7-8℃, and plant them outdoors after the weather warms up in spring.

2. Softwood cuttings: Softwood cuttings are the most widely used method for chrysanthemums. Mostly from April to May, cut 8-10 cm soft shoots as cuttings. At a temperature of 18-21℃, most varieties root in about 3 weeks and can be transplanted into pots in about 4 weeks.

3. Field cuttings: For field cuttings of chrysanthemums, the medium can be garden soil mixed with 1/3 rice-hull ash. Build a reed-screen shed on a raised bed for shade. For a fully exposed cutting bed, if automatic misting equipment is available, no shading is needed.

4. Leaf-bud cuttings: Leaf-bud cuttings of chrysanthemums involve cutting a single leaf with an axillary bud from a branch and inserting it. This method is only used to propagate rare varieties.

5. Division: Division of chrysanthemums is generally done around Qingming. Dig up the plant and separate it along the natural form of the roots, keeping roots on each division, then plant them separately in pots.

6. Grafting: Collect mugwort seeds in late autumn and sow them in a greenhouse in winter, or raise seedlings in a hotbed in March. In late April, when the seedlings are 3-4 cm tall, move them into pots or the field, and carry out cleft grafting on a sunny day.

7. Layering: Layering propagation of chrysanthemums is used only when propagating bud-sport portions.

8. Seeds: Chrysanthemum seeds germinate slowly above 10 degrees Celsius, with an optimal temperature of 25℃. Sow thinly between February and April, and under normal conditions most can bloom in the same year.

How to Grow Potted Chrysanthemums?

1. Potting soil: Chrysanthemums have broad adaptability to soil acidity and alkalinity and can grow in soil from slightly acidic to slightly alkaline, requiring a pH value between 5.5 and 7.0. Fertile sandy soil should be chosen. Start with a small pot and then move to a larger one, repotting 2-3 times, and by July the final pot can be set. For the final potting, a mixed soil can be made from 6 parts leaf mold, 3 parts sandy soil, and 1 part cake fertilizer residue. After watering thoroughly, place it in a cool spot, and move it to a sunny spot once the plant is growing normally.

2. Temperature: The key to growing autumn chrysanthemums well is first of all to get them safely through the winter. Because the climate conditions in northern and southern China differ, the overwintering management methods for autumn chrysanthemums also differ. In some southern regions, after the flowers of field-grown chrysanthemums fade and the stems and leaves gradually wither, the chrysanthemum plants can be cut off 15 cm above the ground, given one overwintering watering, and then covered with fallen leaves and dry soil so that the stems and leaves are exposed 3-5 cm to allow ventilation, and they can then overwinter safely.

3. Light: The chrysanthemum is a typical short-day flower. Only when the daily sunshine is relatively short does it form flower buds and bloom. Under longer sunshine, it only grows stems and leaves and cannot form flower buds. Generally, during the vegetative growth period it needs 14.5 hours of sunshine per day, and during the flower bud differentiation period it needs 12 hours of sunshine per day.

4. Water: Water management during the chrysanthemum's growth period must follow the principle of “water promptly when dry and drain promptly when waterlogged”. Also, sufficient water must be ensured before and after the bud-setting period. Watering can also be combined with fertilizing, and attention must be paid to “alternating wet and dry”, that is, it should be neither half-dry and half-wet, nor too dry or too wet. Also, spray the leaves with leaf-surface water once each morning and evening every day.

5. Fertilizing: In addition to applying sufficient base fertilizer, chrysanthemums must not be given too much or too early topdressing, otherwise it will cause root damage and leaf drop. But after the Start of Autumn, from the beginning of bud setting until the buds appear, fertilizer and water must be sufficient. Generally, apply a thin bone-chip and sauce-residue water once a week. When the buds are about to open, apply one more round of superphosphate or 0.1% potassium dihydrogen phosphate solution, and the flowers will be even more vivid. After each fertilizing, water and loosen the soil promptly to aid aeration.

6. Pruning: During the vigorous seedling stage of chrysanthemums, many axillary buds sprout and need to be pinched off promptly with the fingers; otherwise they will consume a large amount of nutrients and grow many small branches that bear small flowers, making the plant look messy and disorderly. During the bud-setting period, side buds sometimes appear on the small branches below the terminal bud. Apart from those that need to be kept, the side buds should also be removed early with tweezers to promote the plumpness of the terminal bud.

7. Pests and diseases: The main diseases of chrysanthemums include rust, black spot, and gray mold. Rust harms leaves and stems, with leaves suffering the most; it can be sprayed with a 500-fold dilution of 65% zineb wettable powder. Black spot mainly harms leaves and can be controlled by spraying an equal-part Bordeaux mixture. Gray mold harms flowers, leaves, stems and so on; in the early stage of onset, spray with a 500-fold dilution of 65% zineb wettable powder.