When to Plant Chrysanthemums? A Detailed Guide to the Latest Planting Times

The chrysanthemum is the third of China's top ten famous flowers and one of the Four Gentlemen of Flowers (plum blossom, orchid, bamboo and chrysanthemum). In plant taxonomy, it is a perennial herbaceous plant with persistent roots of the genus Chrysanthemum in the family Asteraceae, also known by other names such as Shouke, Jinying, Huanghua and Qiuju. In ancient myths and legends, the chrysanthemum was also given the meaning of good fortune and longevity, and it has extremely high cultivation value. Let us take a look below at when chrysanthemums should be planted!

Planting Time for Chrysanthemums

Chrysanthemums can be propagated in two ways: vegetative propagation and seed propagation. Vegetative propagation includes cuttings, division, grafting, layering and tissue culture, and is usually done mainly by cuttings. If you choose to sow chrysanthemum seeds, it is best to do so in spring. Chrysanthemum cuttings are taken in spring and summer or in late autumn after flowering, while division is best done in late autumn after flowering. Chrysanthemum root division and transplanting should be done before May 15, while chrysanthemum cutting and transplanting should be done before June 16.

Propagation Methods for Chrysanthemums

1. Bud cuttings: In autumn and winter, cut off the outer shoot buds of the plant for cuttings. The standard for selecting buds is that they are relatively far from the plant and plump at the tip. After selecting the buds, strip off the lower leaves and insert them at a plant spacing of 3-4 cm and a row spacing of 4-5 cm into flower pots or coarse sand in a cutting bed inside a greenhouse or plastic tunnel. Maintain a room temperature of 7-8 degrees C, and plant them outdoors after the weather warms in spring.

2. Field cuttings: The medium for field cuttings can be garden soil mixed with 1/3 rice husk ash. Build a reed curtain shed on a raised bed for shade. A fully exposed cutting bed with automatic misting equipment does not need shading.

3. Division: Chrysanthemum division propagation is generally done around Qingming. Dig up the plant, separate it along the natural form of the roots while keeping the roots attached, and plant them separately in pots.

4. Grafting: Chrysanthemums can be grafted using Artemisia annua or Artemisia carvifolia as rootstock. Collect mugwort seeds in late autumn, 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 perform cleft grafting on a sunny day.

5. Seeds: Chrysanthemum seeds germinate slowly above 10 degrees C, with an optimum temperature of 25 degrees C. Sow sparsely between February and April. Under normal conditions, most can bloom in the same year.

Cultivation Techniques for Chrysanthemums

1. Potting soil: For chrysanthemum cultivation, fertile sandy soil should be used. Start with a small pot and then move to a larger one, repotting 2-3 times, and the pot can be finalized in July. For the final potting, a mixed soil can be prepared with 6 parts leaf mold, 3 parts sandy soil and 1 part cake fertilizer residue. Water thoroughly and place in a cool place. After the plant grows normally, move it to a sunny place.

2. Watering: In spring, when chrysanthemum seedlings are small, water sparingly. In summer, when the seedlings have grown larger, water once in the early morning and water again in the evening as a supplement, and use a watering can to spray water on the chrysanthemum branches, leaves and surrounding ground to increase environmental humidity. Before the Beginning of Autumn, properly control water and fertilizer to prevent the plant from shooting up and growing wildly. After the Beginning of Autumn and before flowering, increase the amount of watering and begin fertilizing, gradually making the fertilizer solution stronger. In winter, the flowering branches basically stop growing, the plant's water consumption decreases noticeably, and evaporation is also low, so watering must be strictly controlled.

3. Fertilizing: When chrysanthemum plants are planted out, sufficient base fertilizer should be applied in the pot. Afterward, apply a nitrogen fertilizer once every 10 days. After the Beginning of Autumn, from flower bud differentiation to visible buds, apply a slightly stronger fertilizer solution once a week. When the buds are about to open, apply one more strong fertilizer solution and then pause fertilizing. If at this time you can apply superphosphate or a 0.1% potassium dihydrogen phosphate solution once to the chrysanthemums, the flowers can bloom more vividly.

4. Pinching: When the chrysanthemum plant grows to more than 10 cm tall, begin pinching. When pinching, keep only 4-5 leaves at the base of the plant and remove all the upper leaves. When 5-6 new leaves have grown, pinch out the growing tip again so that the plant retains 4-7 main branches, and promptly remove branches and buds that grow later. Pinching can cause the plant to branch and effectively control plant height and shape. At the final pinching, carry out shaping pruning on the chrysanthemum plant, removing excess branches and branches that are too vigorous or too weak, keeping only 3-5 branches.

5. Bud thinning: When chrysanthemums form buds in September, remove the buds at the lower part of the plant, leaving only one bud at the top of each branch.

Pest and Disease Control for Chrysanthemums

1. Leaf spot disease: Leaf spot disease, also known as leaf blight, begins in mid-to-late April and damages the leaves. After harvesting the flowers, cut off the aboveground parts of the plants and burn them in a concentrated manner. In the early stage of the disease, remove the diseased leaves and alternately spray with 1:1:100 Bordeaux mixture and 50% thiophanate 1000 times solution.

2. Fusarium wilt: Fusarium wilt begins from early June to early July, and becomes severe after flowering, damaging the whole plant and rotting the roots. Select disease-free old roots for seed retention, practice crop rotation, make high beds, open deep furrows, reduce humidity, pull out diseased plants, and scatter lime powder in the diseased holes or drench with 50% carbendazim 1000 times solution.

3. Pests: Chrysanthemums are planted throughout the year, providing pests and mites with abundant food and habitat. Whether cultivated in net houses or in the open field, they cannot escape damage from pests or mites. The important pests on chrysanthemums include aphids, thrips, tobacco cutworm, beet armyworm, tomato fruitworm and two-spotted spider mite, among others. The minor pests include cutworms, inchworms, leafminers, whiteflies, tussock moths, mealybugs and fine mites, among others. The variety can be said to be quite numerous.

4. Weeds: Chrysanthemum cultivation is mostly open-field cultivation and is rotated with paddy fields. Generally, the common dryland weeds found in paddy-dryland rotation fields will all occur in chrysanthemum fields. The competitive harm of weeds is related to the cultivation method of chrysanthemums, the weed composition, density, competition period and environmental factors. The competition of weeds for water, nutrients and light can directly cause poor growth and reduced quality of chrysanthemums, and is unfavorable for field management operations.