How to plant zinnia seeds? Detailed explanation of sowing methods
Zinnia generally refers to Zinnia elegans, an annual herbaceous plant of the genus Zinnia in the Asteraceae family, native to Mexico. It has single-petaled, double-petaled, curled-leaf, wrinkled-leaf and various differently colored horticultural varieties. It is widely cultivated throughout China and sometimes becomes wild. It can be used according to height in flower beds, flower borders and flower strips, and is also often used for potted plants. Now let us take a look at how to plant zinnia seeds!
Seed selection
The seeds of zinnia have a lifespan of 3 years and a germination rate of about 60%. Try to choose plump seeds from the previous year to increase the seed germination rate. To save zinnia seeds, do it when the outer ring of petals begins to dry up and the middle ring of petals begins to lose color. Cut off the flower heads, sun-dry them, remove impurities and store them.
Disinfection treatment
Before sowing zinnia, the soil and seeds must undergo strict disinfection treatment to prevent pests and diseases during the growing period. For seed disinfection, soak the seeds in 1% potassium permanganate solution for 30 minutes. The substrate is mixed with 2 parts leaf mold, 1 part river sand, 2 parts peat and 2 parts perlite. It can be disinfected with 0.05% potassium permanganate or 1000 times formalin. The soil can be treated by high-temperature fumigation to kill pathogens, pests and weed seeds in it.
Sowing time
The sowing time of zinnia depends on the desired flowering time. Generally, sow in a greenhouse 2 to 3 months in advance. Direct sowing in the open field should be after the severe cold of early spring, otherwise the seedlings will develop poorly. If used for autumn flower beds, it is better to sow in summer. Spring sowing is carried out from March to April, transplanted when there are 4 to 5 leaves, planted out in early June, and blooms from July to frost.
Sowing method
Zinnia seeds can be sown in holes or broadcast. Because it is a light-avoiding flower seed, after sowing it must be covered with a layer of vermiculite. At a temperature of 21 to 23°C, it can germinate in 3 to 5 days. The germination period does not require light. After germination, the seedbed should maintain a moisture content of 50 to 60%, and must not be too wet, so as to avoid root rot or damping-off disease.
Seedling management
After the zinnia seedlings grow 1 true leaf, divide and transplant the seedlings once. The root system of zinnia is not well developed and has few lateral roots. Generally, when there are 2 true leaves, transplant and plant them into pots. When transplanting, they should be moved with soil. The transplanting substrate should be loose, fertile and well-drained. It can be prepared with 3 parts pond mud, 1 part leaf mold and 1 part decomposed manure compost. The planting depth is 0.5 cm below the cotyledons. After planting, press the soil lightly and water thoroughly.