How and when to grow asparagus

Asparagus is a perennial plant and once mature, it can be harvested continuously for many years. It has a thick root system and tender stems that grow in the spring. Asparagus prefers full sun and well-drained soil. It has certain requirements for the pH value of the soil, usually between 6.0 and 7.0. Let’s learn about the cultivation methods and time of asparagus.

1. Asparagus cultivation time

Asparagus is usually planted in the spring.

Asparagus will produce new stems 2 to 3 times or more each year. The young stems that grow in the spring are often used as food, and their growth relies on nutrients stored in the roots from the previous year. The growth and yield of young stems are directly proportional to the number of stems formed in the previous year and the luxuriance of branches and leaves. As the plant ages, the number of young stems grown each year and the yield will gradually increase. However, as the rhizomes continue to branch, the plants will gradually age, the above-ground stems will become thin, and the yield and quality of the tender stems will gradually decrease. Generally speaking, the peak production period of asparagus is 4 to 10 years after planting.

For asparagus grown outdoors, it is suitable to raise seedlings in April and May and plant in July and August. If it is planted in a greenhouse , seedlings can be raised in August and September and planted in October.

2. How to grow asparagus

1. Seedling cultivation

The shell of asparagus seeds is thick and hard, and water cannot penetrate easily, so they usually need to be soaked in warm water at 25 to 30 degrees Celsius for 4 to 5 days before sowing. The germination temperature should be controlled between 25 and 30 degrees Celsius. Commonly used seedling raising methods include sunbed seedling raising, small arch shed seedling raising and open field seedling raising.

1.1 Establishing the Seedbed

Depending on the geographical location, make a seedbed of a certain size, deep plow the soil, harrow it and level it. Apply 100 kg of well-rotted manure and 1.5 kg of triple compound fertilizer per 10 square meters, turn it into the soil to a depth of 15 cm, mix well, level and water, and sow after the surface is slightly dry.

1.2 Seeding

Before sowing, soak the seeds in warm water at 25 to 30 degrees Celsius for 5 days, changing the water 1 to 2 times a day to ensure that the seeds fully absorb water. The sowing depth is about 3 cm. Sow the asparagus seeds individually after digging trenches in the seedbed and watering it. The sowing density is 15 to 20 cm between rows and 5 cm between plants. After sowing, cover the seeds with 2 to 3 cm of soil and press them lightly the next day to make the seeds in close contact with the soil to facilitate water absorption and moisture retention. To prevent underground pests, poison bait can be placed in the sowing furrow.

1.3 Management after sowing

Asparagus seedlings will emerge in about 10 to 15 days after sowing. During this period, if the soil moisture is insufficient, water should be applied in time; if the ground temperature is insufficient, be careful not to water too much, so as not to lower the ground temperature and affect emergence. Generally, spray water to keep it moist. Water the seedlings once when they are 10 cm tall. After the asparagus seedlings have grown, weeds will also grow and should be removed in time to avoid competing with the asparagus seedlings for sunlight, water and nutrients. Water should be controlled 10 to 15 days before transplanting to harden the seedlings and improve the survival rate of transplanting.

2. Colonization

2.1 Selection of planting site

The land for planting asparagus should be selected where the soil is deep, loose, fertile, has good air permeability and water infiltration, has a low groundwater level and has irrigation and drainage conditions. Old orchards, mulberry gardens and other places should be avoided because these places are prone to asparagus being infected with purple feather disease.

2.2 Planting time

In spring, it is usually carried out before the asparagus seedlings sprout, and the seedlings grown in June or July of the previous year are used for transplanting; in summer, the seedlings grown in March or April of the current year can be used; in autumn, in the absence of protective measures, the latest planting time should not be later than September 15, and the seedlings grown after April of the current year can be used.

2.3 Planting density

Green asparagus cultivation does not require soiling and can be grown at a higher density. The appropriate density is 37,500 to 45,000 plants per hectare, which means that when the row spacing is 1 meter, the plant spacing should be 20 to 25 centimeters.

2.4 Planting method

Asparagus prefers a loose and fertile soil environment. The soil should be deeply plowed once before planting, and then raked and leveled after plowing. Dig trenches with a row spacing of 1 meter, with a depth of 30 cm and a width of 40 cm. After backfilling the trenches to 15 cm, apply 30 to 45 tons/hectare of manure and 600 kg/hectare of triple compound fertilizer (N:P:K ratio of 15:15:15). Mix the fertilizer with the 15 cm soil in the trench, backfill the soil again to make the trench about 7 cm deep, and then water it to make it compact. Dig a shallow trench in the middle of the ditch and plant the asparagus seedlings according to the predetermined spacing. The total depth after planting should be 10 to 15 cm below the ground. The roots should be stretched during planting and water should be applied in small amounts while planting.

The above is an introduction to the cultivation time and key points of asparagus. Asparagus is a health vegetable with good nutritional value, and its market prospects are currently favored by many people.