African Marigold Planting Methods and Key Technical Points

African marigold is a perennial herbaceous flower of the Asteraceae family with a perennial root system, native to South Africa. In recent years it has been introduced into China from abroad, and it is loved by many people for its beautiful appearance. Below let us take a look together at the planting methods for African marigold!

1. Growth habits of African marigold

African marigold likes sunlight, is moderately cold-tolerant, and can endure low temperatures of -3°C to -5°C. It is drought-tolerant and prefers loose, fertile sandy loam. It performs even better in moist, well-ventilated environments. It has strong branching and does not require pinching. It blooms early and has a long flowering period. Low temperatures favor flower bud formation and blooming. In regions with a mild climate, it can grow year-round.

2. Cutting propagation of African marigold

1. Cutting method: During cutting propagation, the cuttings need to be planted in a rooting seedbed within 12 to 24 hours after being taken. If time does not allow, they need to be temporarily stored at a temperature of 7°C to 10°C. A higher substrate temperature (20°C to 23°C) is beneficial for rooting of the cuttings. After rooting, the temperature can be lowered. In addition, dipping in rooting hormone can stimulate earlier rooting and improve rooting uniformity.

2. Cutting management: In the early stage of cutting (within 3 to 5 days), the mist system needs to be kept running for long periods. Be careful to prevent unrooted cuttings from wilting, and reduce the frequency of misting at night. After rooting, fertilizer at a concentration of 75 ppm to 100 ppm can be applied, and as the root system grows, the fertilizer concentration should be gradually increased to 150 ppm. At the same time, keep the substrate moderately moist and avoid over-saturation. This can not only prevent leaf yellowing caused by iron loss, but also reduce the occurrence of diseases.

3. Planting techniques for African marigold

1. Sowing method

[Time]November to January.

[Plug tray]According to the purpose of production, choose 72, 128 or 200 plug trays.

[Method]Dibbling, one seed per cell.

[Substrate]Mix peat : vermiculite = 3:1, with a pH value of 6.2-6.5. Too low a pH will lead to poisoning by certain metal elements (such as iron, sodium, etc.). The day before sowing, drench the plug tray thoroughly and set aside for use.

[Covering material]Use medium-grade vermiculite to cover the seeds, which facilitates aeration and drainage. After sowing, to ensure the temperature and humidity needed for germination, plastic film can be used to cover the plug tray.

2. Germination stage, phase 1: From sowing to emergence of cotyledons, about 6-8 days. At this time, the plastic film can be removed.

[Substrate]Substrate moisture content 80%±5%.

[Humidity]70%-80%.

[Temperature]20°C-25°C.

3. Germination stage, phase 2: From the appearance of cotyledons to the complete development of cotyledons, completing the germination process.

[Temperature]Lower the temperature to 18°C-25°C.

[Substrate]Keep moist (moisture content about 80%). When necessary, water can be sprayed onto the seedling tray in the form of mist.

[Fertilizer]Apply 50-75 ppm (EC value 0.8) nitrogen, phosphorus and potassium compound fertilizer.

[Light]No more than 25000 lux. Supplemental lighting can make the plants bloom earlier.

4. Germination stage, phase 3: From the appearance of the first true leaf until the plug seedlings reach standard specifications (more than 4 true leaves, with roots filling the cells).

[Temperature]18°C-20°C.

[Water]Moderate moisture content, avoiding the substrate being too dry or too wet.

[Fertilizer]Apply 150 ppm nitrogen, phosphorus and potassium compound fertilizer once every 3-4 days (EC value 1.0-1.2). Ammonium nitrogen fertilizer is beneficial for the growth of aboveground stems and leaves, while nitrate nitrogen fertilizer is beneficial for root development.

[Light]Same as phase 2.

[Control]Under normal circumstances, African marigold plants grow relatively robustly and rarely become leggy. To prevent some varieties from growing too tall, B9 or PP333 can be used at the end of phase 3 to control plant height.

5. Germination stage, phase 4: The transitional growth stage between the end of plug seedling cultivation and potting up or sale of the plug seedlings.

[Temperature]Lower the growing temperature to 17°C-18°C. From the beginning of this period until before flowering, the plants must go through a low-temperature stage of 5°C-8°C at night, which is beneficial for smooth flower bud differentiation and flowering of the plants.

[Water and fertilizer]Control water and excessive ammonium nitrogen fertilizer to avoid leggy growth of the plants. Keep the substrate on the dry side, strengthen ventilation and light, and enhance the resistance of the plants.

6. Management after potting up: Generally, the plug seedling period for African marigold is 10-12 weeks. After the plug seedling period ends, they should be potted up in time, otherwise the flowering period will be advanced.

[Substrate]Mix peat : vermiculite : garden soil = 1:1:1, with a pH value of 6.2-6.5.

[Temperature]18°C-23°C during the day, 10°C-18°C at night. Too high a temperature will make the flowers smaller, and too low a temperature may cause leaf yellowing in some types.

[Water]Keep the substrate moisture alternating between dry and wet, but do not let the substrate become too dry or too wet. Excessive moisture will lead to leggy growth of the plants or cause diseases.

[Fertilizer]Apply 150-200 ppm nitrogen, phosphorus and potassium compound fertilizer (EC 1.2-1.4).

7. Pests, diseases and control

[Pests]African marigold is simple to cultivate and manage, with relatively few pests and diseases. The common pest is aphids, which can be controlled by spraying the plants with 80% dichlorvos emulsifiable concentrate at 800-1000 times dilution or Yibianjing at 1000 times dilution.

[Diseases]One common disease is root rot, mostly caused by excessive watering. It can be prevented by properly controlling water and keeping the substrate slightly moist to on the dry side. Once root damage is found, repot in time and replace the substrate. The second is yellow leaves. The causes of yellow leaves and control measures are as follows: ① Yellow leaves mainly occur on young leaves and often show spots. The cause is that the substrate pH value is too low, causing iron poisoning. This can be adjusted by watering with an appropriate concentration of limewater to adjust the substrate pH value. ② Too low a temperature during the seedling stage; the nighttime temperature can be appropriately increased. ③ Insufficient nitrogen fertilizer application; the amount of nitrogen fertilizer can be appropriately increased.