Detailed Explanation of the Key Cultivation and Management Techniques for White Clover
Just hearing the name clover, we should know that it is a grass that grows three leaves. Clover is fairly common in our country, and it is generally used to decorate lawns, embankments and so on, so its greening role is very great. Secondly, it also has certain medicinal value and is a relatively common Chinese herbal medicine.
What Is Clover
The genus Trifolium mainly includes three categories: the genus Trifolium (currently the most authentic clover), the genus Oxalis, the genus Medicago, and others. White clover (also known as “white trefoil”), a short-lived perennial herbaceous plant of the Fabaceae family and the genus Trifolium, has a growth period of up to 5 years. Its species are found throughout the world, with more than 300 species. White clover is an excellent forage grass, rich in protein and minerals, resistant to cold and heat, and able to adapt to both acidic and alkaline soils. It is a species in this genus with great potential for promotion in our country. It can be used as green manure, an embankment protection grass species, lawn decoration, as well as a nectar source and medicinal material. The occasionally appearing special variant with four leaves symbolizes the “lucky clover.” The species more widely cultivated in our country are red clover, white clover and hybrid clover.
Clover is a perennial herbaceous plant. The plant is low-growing, 25-40 cm tall. It has a taproot, and the roots have the characteristic of symbiosis with rhizobia; the root's tillering ability and regeneration ability are both strong. It has many branches, and the creeping stems grow along the ground; where the internodes touch the ground they take root and sprout new shoots. The compound leaves have three leaflets; the leaflets are obovate or obcordate, wedge-shaped at the base, blunt or slightly concave at the tip, with fine serrations along the edges, and a “V”-shaped white mark in the center of the leaf surface; the stipules are elliptical and clasp the stem. It blooms in summer and autumn, with a head-like raceme, spherical, with a long peduncle, white flowers, occasionally pale red. It blooms while setting seed, the seed maturation period is not uniform, and the seeds are very small.
Clover has strong vitality, is low and creeping, tolerant of mowing, and also has self-seeding ability, so its coverage effect is good. Because it has nitrogen-fixing ability, it does not require much fertilizer. However, during long droughts without rain, attention should be paid to timely watering to resist drought. The leaf clusters are low, it flowers abundantly, and the green period is long, so it is often used in flowered lawns and can be mixed-sown with Kentucky bluegrass, red fescue and others. It can also be sown alone as flowering vegetation, and is often used for slope greening, having the effect of conserving soil and water. White clover is low-growing, only 30-40 cm tall, so it generally does not need mowing. But it is also tolerant of mowing, and after mowing it can quickly restore the coverage effect.
Cultivation Techniques for Clover
1. Land preparation
White clover seeds are small, and the seedlings have poor soil-emergence ability, so before sowing the land needs to be leveled and raked fine to facilitate emergence. In areas with heavy, clayey soil and high rainfall, trenches should be opened and beds made to facilitate drainage. 2. Sowing
Autumn sowing from September to October is best, and spring sowing from March to April is also possible. In the middle and lower reaches of the Yangtze River, sowing is generally done around mid-September, with a sowing rate of 10-15 grams per square meter, by broadcast sowing or drilling, with a row spacing of 30 cm for drilling. It is better to mix the seed with an equal amount of fertile soil before sowing. After sowing, keep the soil moist; seedlings will emerge in 3-5 days, and full emergence occurs in ten days.
3. Fertilization
Applying a small amount of nitrogen fertilizer is beneficial for strong seedlings. Fertilization should focus mainly on phosphorus and potassium fertilizers, with an appropriate amount of nitrogen fertilizer. Before sowing, apply 20-25 kg of superphosphate per mu as well as a certain amount of barnyard manure as base fertilizer. After emergence, if the plants are short and the leaf color is yellow, apply a small amount of nitrogen fertilizer, 10 kg of urea per mu or a corresponding amount of ammonium sulfate, to promote strong seedlings. In March, apply a topdressing of compound fertilizer once, applying 30-40 kg per mu in trenches at the root zone of the lawn, then water, which can significantly enhance growth, improve the ability to resist high temperatures, and reduce grass death.
Key Management Points for Clover1. Field management
White clover grows slowly at the seedling stage and is easily harmed by weeds, so during the seedling stage weeds should be removed frequently, and this is even more so for spring-sown clover. When the grass layer is 20-25 cm high, it can be appropriately mowed to enhance ventilation and air permeability. After mowing, its regeneration ability is strong, and it can quickly form a second cutting of grass layer. In the high-temperature season, white clover stops growing. In the 2-3 years after the grass layer cover has formed, large weeds should be removed in time. If missing plants occur due to high-temperature summer drought, reseeding can be done in autumn to restore the neatness of the lawn. White clover has few diseases, though brown spot and powdery mildew sometimes occur; it can first be mowed, then controlled with Bordeaux mixture, lime sulfur mixture or carbendazim and the like. White clover has relatively many insect pests, especially white grubs and snails, which cause serious damage. For white grubs, the selected pesticide is 50% isofenphos-methyl at 3 kg per mu mixed with 3000 kg of water, sprayed in mid-April and from late July to early August respectively; after spraying, water promptly so that the pesticide solution soaks through 7-10 cm of the ground, and the white grubs die after contact with the treated soil. This method is still not ideal for a small number of older larvae. For snails, spraying insecticides has very poor control effect, but using snail-killing granules scattered in the lawn in the evening at a dosage of 1.5-2 grams has a very good effect, with a mortality rate of more than 90%.
2. Winter management
Remove dead branches and dead leaves. During the growth process of white clover, as new and old branches and leaves continuously renew and grow, a relatively thick layer of dead branches and leaves will gradually form on the ground surface, which is a place for pathogens and insect eggs to overwinter. Removing dead branches and dead leaves will play a very good inhibitory role in the occurrence of pests and diseases in the coming year. Before the cold winter arrives, water once for overwintering (penetrating about 15 to 20 cm), and combined with freeze protection apply organic fertilizer once, which not only provides sufficient nutrients for the lawn's growth in the coming year, but also has a certain heat preservation effect. In this way, through winter fertilizer and freezing water, not only can the soil nutrient and moisture conditions be improved and safe overwintering ensured, but it also creates good conditions for the lawn's green-up growth the following year.
Planting Time for Clover
Before sowing, a seed germination test should be carried out to understand the germination rate and germination vigor of the seeds. The germination rate of clover seeds is 75%-85%, and their germination vigor is very strong; after sowing, all can germinate in 2-3 d, and all can emerge in 4-5 d. Before sowing, clover rhizobia can be used to inoculate the seeds; after inoculation with rhizobia, clover grows vigorously and its nitrogen-fixing effect is enhanced. The inoculation method is to take clover root nodules, crush them, add water to dilute, and mix with the seeds, with the criterion being that the seeds are thoroughly moistened. Commercially available clover rhizobia inoculant can also be used for seed dressing.
Clover can be sown in spring or autumn, in late March in spring and in mid-September in autumn. The south is mainly autumn-sown, while the north is mainly spring-sown. It can also be sown in summer, but after sowing the surface soil must be kept moist or covered with mulch for shade. The sowing rate for establishing a clover lawn is preferably 8-10 g/㎡. Each gram of clover has 1400-2000 seeds; theoretically, 1 seed per square centimeter of soil can meet the need for lawn formation. The actual sowing rate is larger than the theoretical sowing rate.
When sowing, divide the seeds equally according to the plot area and the determined sowing rate, mix the seeds evenly with dry soil or fine river sand, and sow by hand. If establishing a lawn over a large area, a cyclone seeder can be used for broadcast sowing. The sowing depth of clover is 1-1.5 cm. After the seeds are scattered into the seedbed, a lawn rake can be used to rake the seeds into the soil, or fertile soil or substrate can be used to cover them by 1 cm.
In our country, the cultivation of clover is very extensive, and it is planted mainly to green the environment. In fact, in the process of planting clover there are still many cultivation techniques and management skills. Through the above introduction by the editor, everyone must now have a general understanding of this. We hope these methods can help you.