How to cultivate and manage chrysanthemums? Technical key points and precautions

AbstractWinter storage and seedling raising: In late September, use basal shoots for the first round of shoot selection. Spring planting: Choose good-quality ordinary potting soil, do not add fertilizer, water thoroughly in one go, keep the potting soil half-dry and half-moist. Summer pinching: Because flowering periods and growth conditions differ by variety, pinching must be done in stages to prevent "willow-leaf heads" and "capping" phenomena. Autumn care: Strengthen care and management to promote the growth of roots, stems, leaves, and flowers.

I. Winter storage (also called seedling raising)

In late September, use basal shoots for the first round of shoot selection. The part above ground should be 2.5 cm long, with a total length of 5 cm; whether rooted or not is acceptable. Plant about 8 shoots in a pot with a mouth diameter of 22 cm; if the pot is less than 22 cm, plant about 5 shoots, then label them properly.

During winter storage, pay attention to the following issues:

1. Soil: Use soil that has previously been used for growing flowers; it will not be too fertile and will not make the chrysanthemum seedlings grow too vigorously.

2. Water: After inserting the cuttings, water thoroughly in one go, then observe dryness and moisture; after they survive, drain excess water.

3. Light: Cuttings should only receive light after about 10 days; too early exposure to light makes disease easy.

4. Temperature: The most suitable temperature for cuttings is about 5-10 degrees, which can keep the plants from growing.

5. To prevent the cuttings from wilting, the basal shoots should first be soaked in cooled boiled water, then planted.

II. Spring planting

Around May 1, place the surviving cutting seedlings outdoors in a ventilated, sunny place for about a week. Divide the seedlings and place them into pots with a diameter of 22 cm, using good-quality ordinary potting soil. Fill about half the pot, do not add fertilizer, keep the protective root soil, trim excess fibrous roots and retain 3-4 cm. Water thoroughly in one go; afterward drain excess water to prevent excessive growth, keeping the potting soil half-dry and half-moist.

III. Summer pinching

Summer pinching can better renew the plant; because flowering periods and growth conditions differ by variety, pinching must be done in stages. Staged pinching is used to control the flowering period and height of chrysanthemums and can effectively prevent "willow-leaf heads" and "capping" phenomena. To better help chrysanthemum seedlings grow new buds and develop new shoots, there are the following three situations:       

1. Varieties with poor growth, short plants, or late flowering periods, such as Quanxiang Chongtian, should be pinched in late May.

2. Ordinary varieties and mid-flowering varieties should be pinched around early June.

3. Varieties with very good growth, tall plants, or early flowering periods, such as Guohua Jiazi, can be pinched around mid-June.

During summer pinching, pay attention to the following points:

1. When pinching, be careful to retain new leaves and branches; about ten new leaves should be retained. Maintain top growth so that rhizomes and new buds emerge faster. Remove all old leaves at the bottom so the chrysanthemum seedlings can carry out photosynthesis, receive light, and be ventilated. If there are too many root buds, remove the side buds beside the mother plant. Conversely, if the mother plant grows weakly, apply an appropriate amount of quick-acting fertilizer to make the seeds sprout.

2. After late July, when newly grown chrysanthemum seedlings are about 10 cm tall, select plants and plant them in place. Use a pot with an inner diameter of 20 cm for single-stem chrysanthemums, a 22-24 cm pot for pin-shaped chrysanthemums, and a 30 cm diameter pot for those with more than 9 heads.

3. By the end of June, chrysanthemum seedlings that have already grown to 10 cm and taken shape can have their center bud removed and the bud head replaced; those with strong growth can be trained into the three-branch, nine-top form, while those with poor growth can be separately cultivated into single-stem chrysanthemums.

4. From late August to early September, when willow-leaf buds are found, remove them promptly; leave only the first side bud alone, otherwise flowering will be affected.

IV. Autumn care (also called autumn management)

The key to chrysanthemum growth and development lies in autumn care; care and management should be strengthened to promote the growth of roots, stems, leaves, and flowers.

1. Potting up: In late July, change the pots and then apply base fertilizer. Note: Varieties with thick, large, full, and plump petals like heavy fertilizer, while varieties with thin, wilted petals are not suitable for heavy fertilizer; when transplanting into pots, do not leave excess branches and fibrous roots. During hot and rainy weather, chrysanthemum seedlings easily develop root rot, so fill the pot with only half the soil; it is best to place the pots in a staggered arrangement so the chrysanthemum seedlings receive light and ventilation; pay attention to preventing and controlling black spot disease, aphids, powdery mildew, yellow spot disease, and other pests and diseases.

2. Cut off the mother plant: Choose to complete this around early August.

3. Fill soil: After removing the mother plant, fill the soil to about thirty percent; for ordinary varieties, fill with fertile soil; for varieties with good growth, fill with heavy fertile soil; for those with poor growth, fill with ordinary soil.

4. Staking and tying: About 7 days after filling soil, stake and tie in batches according to the height of the chrysanthemum seedlings until flowering.

5. Topdressing: In mid-September, after the plants have taken shape, apply topdressing, then fill with twenty percent heavy fertile culture soil. In early October, apply potassium dihydrogen phosphate or urea or a mixture of both as a water application once every 7 days, or choose to spray the leaf and branch surfaces 3-4 times in the evening. Conversely, if the leaf veins are found to become darker and wider, or even the leaves become stiff and make noise when the wind blows, then fertilization must not continue; once the flower buds bloom, fertilization can be stopped.      

6. Bud removal: From mid-September to early October, chrysanthemum plants show buds; remove side buds appropriately. When the buds grow to about the size of a pea, remove them in three rounds in order from top to bottom. It is best to leave 2 side buds below the 4th leaf as a backup in case the main bud develops abnormally.

7. Shaping: Flower receptacles can support varieties with weak growth, and frames can support varieties of the three-branch, nine-top form.

8. Flowering period management: When the buds begin to show color, stop fertilizer and reduce the frequency of watering each day; after full bloom, move them indoors to avoid sunlight. Low indoor temperatures can prolong the chrysanthemum flowering period. Avoid frost indoors to prevent chrysanthemums from frost damage. If the dust on the leaves needs to be cleaned, be careful that the petals do not get wet.