Cultivation and management method of Calendula officinalis

Calendula English name: Calendul Scientific name: Calendula officinalis

Origin: Southern Europe to Iran, the genus: Compositae

Characteristics: One or two-year-old herbs, like strong light, cold-resistant, like cool and moist, afraid of hot, not strict on the soil, adaptability. Plant height 20-35cm, leaves long ovoid, base clasp, flower head, solitary stalk top, flower stems about 6-10 cm, stalk-like flowers single or multiple round, flattened to double-flowered, flowering 11- From December to March-May, it is a good flower bed flower for the winter and spring seasons. Due to the impact of climate on the Jiangsu and Zhejiang regions, it is mainly used in the “New Year's Day” and “Spring Festival”. The “May 1st” is extremely unsatisfactory due to the high temperature. Nowadays, there are mainly famous series such as “Big Stick”, “Black Eye” and “Banquet”. The colors are yellow and orange. The “stick” is 10-14 days earlier than other varieties.

Sowing seedlings: Calendula seed is between 130-170 grains per gram, which is in the shape of a star-shaped moon. Winter and spring flowers are usually used in September-October to solve the flowers in the late winter and early spring, so generally in September. The amount of seeding is large. At present, it is mainly used for bed seeding and box seedling breeding in protected areas. A few professional potted plants are used for commercial seedling seedling raising. The artificial soilless substrate is used. The medium is disinfected, the pH value is 6.0-6.8, and the EC value is 0.5-0.75. Covering with vermiculite after sowing is more beneficial to seed germination. After sowing, the medium humidity is 60-70%, and 8-15 days emerges.

The first stage:

Germinated 4-6 days after sowing, Calendula requires medium humidity to be dry. Excessive moisture makes it impossible to germinate properly. The temperature is kept at 20-25 ° C, and the calendula is light, no need to shade, such as planting in September, it can be properly shaded for cooling.

second stage:

Moisture is still needed at this stage, but the humidity is lower than the first stage. This way the roots fit nicely into the medium without swaying. As the roots grow down, the cotyledons gradually unfold, and the first pair of true leaves can be fully expanded to start spraying fertilizer, with a concentration of 50 ppm of 20-10-20 water-soluble flower-specific fertilizer.

The third phase:

At this stage, the seedlings enter the rapid growth period, and the requirements for water and fertilizer are high. The water-soluble flower special fertilizers of 50-100ppm20-10-20 and 14-0-14 can be alternately applied to reduce the accumulation of salt ions. In the seedling production, fertilization is better with a small number of times, that is, once every time the water is poured, the fertilizer is poured once, and the water-soluble flower special fertilizer of 50ppm20-10-20 and 14-0-14 can ensure the growth of the seedlings. need. However, watering needs to be alternated between wet and dry, which is beneficial to regulate and promote root growth. The temperature can be appropriately reduced to about 18 °C. At this stage, there are 2-3 pairs of true leaves, the height of seedlings is 3-4 cm, and the roots can grow to 3- 5cm.

The fourth stage:

This stage is the refining period. Since the roots of the seedlings are basically long and there are 3 pairs of true leaves, it is necessary to pay attention to controlling the water. The special fertilizer for flowers of 14-0-14 is used. The temperature and humidity are slightly lower than the previous stage. Ventilation to prevent lengthy.

Transplant/upper pot: After the refining period, the upper pot can be transplanted. Calendula offspring generally adopts a nutrient meal of 12-13cm diameter, once in the basin, no longer change the basin. If it is used to spread seedlings, it is best to use a tray of 128 or 288 to move the seedlings once and then to the basin. In the upper basin, a small amount of compound fertilizer can be mixed into the medium as a base fertilizer.

Light regulation: Calendula is a hi-light plant. It needs to have enough sunshine for growth and flowering without shading.

Temperature control: The temperature after the upper basin can be properly maintained at around 15 °C. Because the calendula is a cold-season flower, it grows in winter and spring, and does not need to be warmed to the greenhouse, and it does not need to be cooled. As long as proper heat preservation can avoid freezing damage, if the temperature is too low in the growth period after the upper basin, the flowering period will be delayed.

Water and fertilizer management: Water and fertilizer management is mainly the choice of medium. Strict requirements for water retention and drainage. In addition to ensuring that the seedlings have sufficient water and fertilizer, proper drying before watering is also essential. This is more conducive to the growth of the root system. However, the medium cannot be dried out and the plants are withered and died. Topdressing should be carried out by alternate application of 20-10-20 and 14-0-14 flower fertilizers. It is applied every 7-10 days at a concentration of 200-250 ppm. In general producer cost, it is more common to apply compound fertilizer, but 20-10-20 fertilizer should be used less when the temperature is lower in winter. In addition, Calendula officinalis is sensitive to trace elements, which tends to cause chlorosis and yellowing between leaves, and loses ornamental value. Cultivation management: Calendula is generally not required to top, so that the flowers are more neat. Outside the Jiangsu and Zhejiang regions, if you want to keep more branches, use topping and leave 4-5 leaves. Keep warm in the winter, so that it can make its green branches and flowers, but also pay attention to ventilation.

Pests and diseases: The main diseases in the seedling stage include rickets, gray mold, bacterial blight (800-1500 times with Plex, 800-1000 times for chlorothalonil, 500-800 times for prevention); The main diseases are powdery mildew, anthracnose and bacterial blight (1000-1500 times with powder rust, 800 times for anthrax Fame, 1:200 Bordeaux mixture for prevention and control); the main pests are aphids, etc. (40% omethoate) 1000 times for prevention and control).

Quality of the cockroach: the flower begins to develop color until the flowering period is good, and the crown width is between 15-20cm. The plant is neat and the leaves are bright green. It is best not to exceed 12 hours in loading and transportation. If the first flower is not sold, it can be trimmed once to remove the residual flowers and still be sold.