Factors affecting the emergence rate of autumn sowing flower seeds

Autumn is the sowing season for many flowers. Biennial or perennial grasses such as goldfish, carnation, daisy, Yu Mei, etc., are suitable for sowing in autumn. Greenhouse flowers such as Chrysanthemum, cyclamen, Tripterygium, etc., as well as delphinium, gerbera, primrose, begonia and other flowers that are easy to lose the ability to germinate after seed harvest. In order to improve the emergence rate of autumn sowing flower seeds, we must first understand some reasons that affect the emergence rate of flower seeds, so as to take measures to deal with them reasonably.

1. The problem of the seed itself

At present, there are many flower seeds on the market, and some packaging is also very particular about buying domestic seeds or imported seeds. Please pay attention to the production date and shelf life marked on the package. Do not buy the seeds that do not indicate the production date and shelf life; most of the expired seeds have lost their vitality and will not germinate.

In addition, when buying seeds, you should have a basic understanding of them, for example, to know whether the seeds you buy are annual or biennial flowers, perennial flowers, spring flowers or autumn flowers. According to common sense, seeds sown in spring generally blossom in summer and autumn; seeds sown in autumn generally blossom in the following spring and summer (except woody flowers). If it is reversed, it is difficult to achieve the expected flowering goal without certain culture equipment. More attention should be paid to purchased seeds, especially to uncultivated flower varieties.

2. Seed treatment is not in place.

Different treatment methods should be adopted for the seeds of different flowers: the seed soaking method can be used for the seeds that are easy to germinate. For example, a bunch of red seeds can be sowed after soaking in warm water at room temperature of 40 ℃ for a day and night. Hard seeds such as asparagus, peony, Jiulixiang, Bairihong and Daphne had better be soaked in 40 ℃ hot water for about 48 hours and then sowed in basin soil for 20 to 30 days before they could sprout and grow. The seeds of Pearl Plum and Bauhinia which have a short dormant period and are easy to germinate can be sowed directly after soaking in 40 ℃ ~ 60 ℃ warm water for 24 hours. Some flowers, such as cloves, wintersweet and some herbaceous flowers sown in autumn, need to be treated with low temperature (0 ℃ ~ 10 ℃) for a certain time to promote post-ripening to break the dormancy of seed embryos and germinate.

The method is to mix the seeds with sand with 60% humidity, then put them in a plastic bag and place the mouth tightly in a flowerpot, then bury it in an open field deep in 40cm~60cm; you can also put the seeds in a 3 ℃ ~ 5 ℃ refrigerator for 60 to 90 days and sow them in the spring. It can also be sown in autumn so that the seeds can be germinated outdoors by natural freezing in winter and germinated in the following spring. The seeds of some flowers such as tassel, pod and peony have the characteristics of double dormancy of radicle and Hypocotyl, that is, the radicle needs to go through a high temperature stage of 25 ℃ ~ 32 ℃ for 1 ~ 2 months or more to break dormancy. Before sowing, this kind of seeds must be mixed with wet sand for a period of high temperature and then transferred to low temperature. After high temperature treatment, they can sprout quickly in spring.

3. The suitable temperature condition of seed germination was ignored.

The germination of dry seeds must not only have certain water conditions, but also have a certain suitable temperature. For example, the suitable temperature for fragrant snowball germination must be 5 ℃ ~ 20 ℃ Gerbera gerbera germination temperature must be above 20 ℃ ~ 25 ℃, the suitable temperature for primrose germination must be in the range of 15 ℃ ~ 18 ℃, which will affect the emergence rate of flowers, especially the occurrence of seed mildew and rot will greatly reduce the germination rate and seedling rate.

4. The sowing date is unreasonable

All small seeds with loose skin such as chrysanthemum, asparagus, impatiens, hundred-day red, Lingxiao and other flowers are suitable for sowing in late spring; seeds with large particles, solid bark or oily seeds such as rose, rose, pomegranate, kumquat, magnolia and other flowers are suitable for sowing in autumn. Seeds with small particles, thin bark and high temperature should be sown in time after maturity, such as cyclamen, melon leaf chrysanthemum, Zhu Dinghong and other flowers should be sown in early autumn. Flowers such as carnation, tricolor blue, golden melon and Yu Mei should be sown in late autumn.

5. There is a problem with the sowing quality.

There are two methods of flower sowing: open sowing and pot sowing. No matter which method requires loose and ventilated soil, fine particles, sanitary and non-toxic, rich in humus and moderate acid and alkali, it is better to have fertile soil. It is beneficial to the emergence of seeds.

Sowing methods include sowing, strip sowing and hole sowing before sowing, covering the flowerpot with plastic film after sowing or covering the flowerpot with glass to prevent the soil from being too dry and affecting seed germination and emergence. The sowing depth should be about 2.5 times of the flower grain diameter. Small cockscomb, August chrysanthemum, four seasons begonia, melon leaf chrysanthemum and other seeds are mixed with fine sand or soil powder to spread the seeds. During the germination of seeds after sowing, attention should be paid to spraying water to keep moisture, but it is not suitable to spray too much water to prevent the decrease of soil temperature or the adverse effect of retting rotten seeds and seedling fibrous roots to increase the emergence rate.

6. Ignore the influence of light

The sensitivity of seeds to light can be divided into light-positive seeds, light-weary seeds and medium-light seeds. Light-resistant seeds need a certain amount of light to germinate, while light-averse seeds have a certain inhibitory effect on seed germination, and their division is not absolute. Generally speaking, light-loving seeds need not be covered with soil or shallow soil after sowing, and the thickness of soil cover of light-weary seeds with slightly larger seeds is 2-3 times that of seeds.

After sowing, light can increase the temperature of the soil to induce seed germination, especially for seeds breaking through the seed coat and emergence of roots. It not only affects the emergence rate of seeds, but also directly related to the growth of good seedlings, strong seedlings. Therefore, the stage from sowing to transplanting seedlings should be a process from dark to weak light and then to natural light. We should try our best to meet the light needs of flower growth according to different stages of sowing and sprouting.