Key points of maintenance of zinnia

The key points of flower cultivation of zinnia are mainly divided into four aspects: temperature, sunshine, moisture and planting density.

Temperature: hundred-day grass likes to warm to the sun, can not bear the heat, high temperature and cold, the suitable growth temperature is 18-20 degrees Celsius during the day and 15-16 degrees Celsius at night. It grows especially fast in summer.

Sunshine: full sunshine can be used directly, and the sun shines directly. If there is not enough sunshine, the plant is easy to grow, the resistance is also weak, and flowering will also be affected.

Moisture: due to the high demand for light, water is easy to evaporate, so it is necessary to maintain proper humidity and can be watered every day in summer.

Planting density: 18 plants per square meter. The hundred-day grass prefers the dry soil environment and avoids environmental waterlogging. In addition to applying an appropriate amount of chicken manure as the base fertilizer for the plant during planting, the dilute liquid fertilizer should also be applied once a week in the vigorous growth stage, which is a crop that likes nitrate nitrogen, so do not apply ammonium fertilizer such as ammonium sulfate and ammonium bicarbonate. The hundred-day grass is full of sunshine and avoid shade in the environment. Keeping the environment ventilated can prevent overgrowth of plants and reduce the occurrence of powdery mildew. Zi Cao likes warmth and is not cold-tolerant. The suitable temperature for its growth is 20 Mel and 30 degrees Celsius, and the plant dies gradually after frost in autumn.

The maintenance of herbaceous flowers is one of the most important summer flowers in the courtyard with bright colors and long flowering period. It can be used to decorate flower beds, flower borders, cluster planting, strip planting. Herbs annual, 15-60 cm tall, hairy throughout. Leaves opposite, ovate or long elliptic, base clasping. Head, about 4cm in diameter, yellow flowers, flowering in summer and autumn. Achenes are flat. The plant height is 15cm and 60cm, and the florescence is from June to September. Habits: like warmth, light, but also resistant to semi-overcast, drought, avoid heat, wet and waterlogging. It requires fertile soil and good drainage. Maintenance points: it likes light, but also resistant to semi-overcast, in the summer noon, to appropriate shade. It is more drought-resistant, and the soil is watered when it is dry, preferably in the morning and very evening. Fertilization, in the growing period, fertilize once a month, not easy to excessive, otherwise easy to burn. Potted hundred-day grass cultivation and maintenance to order hundred-day grass, also known as step-by-step high, opposite leaf plum, five-colored plum, for Compositae, hundred-day grass is an annual herbaceous flower. The height of the plant ranges from 40 cm to 120 cm, and the stem is erect, covered with short hairs, and the surface is rough. Leaves opposite, ovoid to elliptic, entire, covered with short bristles, leaf base clasping. Heads ranging from 5 cm to 15 cm in diameter, inserted at the top of branches, with long pedicels. The tongue-shaped flowers are multi-whorled, the petals are Obovate, the top is rolled back slightly, there are white, yellow, red, pink, purple, green, orange and other colors, the tubular flowers are concentrated in the center of the disk, the tip of the Corolla is 5-lobed, yellow to orange, and the style is 2-lobed. Inflorescence involucre multi-layered campanulate, basally United. The ligulate flower can also bear fruit, the achene is widely ovate to bottle-shaped, the tip is acuminate, the middle is slightly concave, the achene produced by the tubular flower is oval, flat and small, the fruit ripens gradually from August to October, the seed life is 3 years, and the flowering period is from June to October.

After long-term artificial hybridization and breeding, there are many cultivation types, which can be divided into three types: large flower high stem type, middle flower middle stem type and small flower clump type. Large flowers tall stem type, plant height 90 cm to 120 cm, few branches, terminal inflorescence diameter up to 12 cm to 15 cm, tetraploid varieties 15 cm to 18 cm in diameter. Middle flower in stem type, plant height about 50 cm to 60 cm, more branches, inflorescence about 6 cm to 8 cm in diameter, apically slightly spreading, the whole inflorescence is approximately oblate. Floret cluster type, plant height is only 40 cm, many branches, the number of flowers per plant is also large, but the inflorescence diameter is small, only 3 cm to 5 cm, the ligulate flowers are spreading but not curled, and the inflorescence is spherical in appearance.

A new type of dwarf line was cultivated in the 1970s, with spreading branches in a semicircle, flower diameter of 7 cm to 8 cm, plant height of less than 30 cm, and the shortest mini plant height of only 20 cm, with a flower diameter of about 4 cm. There are also varieties of dwarf large flowers.

Hundred-day prairie is produced in Mexico and other places, and is now widely cultivated all over the world. Strong in nature, strong in adaptability, deep in root system, hard in stem and not easy to lodge. Like sunshine, the number of ligulate flowers increases under the condition of long sunshine. Like warm, not cold-resistant, barren, drought-resistant, avoid continuous cropping, afraid of hot and humid. The land grows well in fertile areas with deep soil layers. The best potted soil is sandy soil with humus, loose and fertile soil and good drainage.

Usually, the sowing method is used to propagate, the optimum temperature for germination is 20 ℃ to 25 ℃, and the seeds germinate in 7 to 10 days. The seed germination requires dark conditions, and the seeds need to be covered with soil after sowing. The time of sowing in the open field should not be too early. If the temperature drops below 15 ℃ after emergence, the seedlings will stop growing and will always grow poorly and form "small old seedlings". When the seedling height is 5 cm to 8 cm, it should be planted separately, and the flower bed can be planted in late May. After the middle of June, lateral branch cuttings can also be taken for propagation, pay attention to shade and rain prevention, so as to avoid cuttings infected and rotten.

The new type of dwarf line and the variety of dwarf large flower should be selected in pot plant. It can be sowed in the greenhouse in early February. In the middle of March, the seedlings were moved into a pot with an inner diameter of 10 cm, with one plant in each pot, and planted in a basin of 18 cm in the first ten days of April. With stable room temperature, adequate light, good ventilation, moderate water and fertilizer, it can blossom and display on May Day.