What kind of environmental conditions does dragon fruit cultivation require?

SummaryThe soil should be a neutral or slightly acidic soil with a high humus content and strong water- and fertilizer-retention capacity. Because dragon fruit has strong adaptability to the environment, it can grow at low temperatures of 0°C to high temperatures of 40°C, but 25°C-35°C is the most suitable temperature for dragon fruit growth and development. Sufficient sunlight can promote the growth rate of dragon fruit. If planted in the open field, it should be watered more in spring and summer, and drainage should be carried out promptly on rainy days, so as to promote better growth and development of dragon fruit.

Dragon fruit is rich in anthocyanins and has antioxidant, anti-aging, and anti-free radical effects. It can also inhibit brain cell degeneration to a certain extent and can prevent dementia.

I. The Growing Environment for Dragon Fruit

1. Propagation time: If choosing cuttings, it is best to do so in spring; if choosing grafting, it is best to do so from March to October.

2. Soil requirements: Dragon fruit has strong adaptability to soil, but it is best to choose a neutral soil or slightly acidic soil with high humus content and good water and fertilizer retention for planting.

3. Humidity requirements: Dragon fruit likes to grow in warm and humid areas. When planting dragon fruit in the open field, water more in spring and summer to keep their root systems growing vigorously. On rainy days, drain the orchard promptly to avoid water accumulation breeding bacteria and causing stem and flesh rot.

4. Temperature requirements: Dragon fruit is a tropical fruit and can grow at low temperatures of 0°C and high temperatures of 40°C, but 25-35°C is the most suitable temperature for dragon fruit growth and development.

5. Light requirements: Dragon fruit likes sufficient sunlight. If there is sufficient light, their growth rate will be very rapid.

II. Precautions for Growing Dragon Fruit

1. Fertilizer application

Dragon fruit is similar to other cactus plants and has a relatively small growth amount. When growing dragon fruit, fertilization should follow the principle of small amounts applied multiple times. The fruit harvest period of dragon fruit is relatively long. During cultivation, organic fertilizer should be heavily applied each year, and nitrogen, phosphorus, and potassium fertilizers should be applied in a balanced way over the long term. If only fertilizers with excessively high nitrogen content such as pig manure and chicken manure are used during cultivation, the plant branches will become thick, dark green in color, and relatively brittle in texture, and are likely to break in strong winds. The fruits produced will be large and heavy, but the quality will be poor, with low sugar content, and some may even have a sour or salty taste.

During the flowering and fruiting period of dragon fruit, in order to promote the accumulation of sugar in the fruit and improve fruit quality, potassium and magnesium fertilizers should be applied more. During the fruiting period, the soil should be kept moist, and the tree dish should be covered with grass or mushroom residue. In drought, irrigate about once every 3-4 days.

For young trees 1-2 years old, mainly apply nitrogen fertilizer, applying it thinly and frequently to promote tree growth. For mature trees over 3 years old, mainly apply phosphorus fertilizer and potassium fertilizer, and control the application amount of nitrogen fertilizer when fertilizing.

The best seasons for fertilizing are the spring new shoot sprouting period and the fruit expansion period. Generally, mix dried oil cake residue, chicken manure, and pig manure in a ratio of 1:2:7 before applying. Each plant should be applied with about 25kg of organic fertilizer each year. Alternatively, in July and October each year and March of the following year, apply 1.2kg of cow manure compost and 200g of compound fertilizer to each dragon fruit plant.

Most of the root system of dragon fruit is distributed in the topsoil layer, so when fertilizing, it is best to use the broadcast application method. Never dig trenches and apply deeply, so as to avoid damaging the root system of dragon fruit. After each batch of young fruit forms, spray the plant outside the roots once with 0.3{bf} magnesium sulfate,  0.2{bf} borax and 0.3{bf} potassium dihydrogen phosphate to improve fruit quality.

2. Watering precautions

Dragon fruit grows better in warm, humid places with sufficient light. During the seedling growth period, the soil throughout the orchard should be kept moist. In spring and summer, the number of waterings should be increased to keep root growth vigorous. During the fruit expansion period, the soil should be kept moist to promote fruit growth.

When irrigating the orchard, do not flood-irrigate for a long time, and do not sprinkle water frequently. Flood irrigation will keep the root system in an oxygen-deficient state for a long time, causing root death. Sprinkling water will lead to uneven humidity and easily induce red spots. On rainy days, drain the orchard promptly to avoid water accumulation in the orchard, which can breed bacteria and cause stem and flesh rot. In winter, control water in the orchard to increase the branches' ability to resist cold.

3. Pruning precautions

After harvesting dragon fruit each year, prune off the branches that have borne fruit on the plant so that they send out new branches again, ensuring the yield for the next year.

4. Key propagation points

At present, dragon fruit is mainly propagated by cuttings and grafting.

Cuttings: It is best to do this in spring. Select better-growing stem segments and cut them into small sections 375px long. After the wounds have air-dried, insert them into a sand bed or directly insert them under the support frame and beside the cement column. After cutting, keep the soil dry; you may refrain from watering at first, then water after 10 days. Generally, they will take root in about 15-30 days. After the roots grow to 3-100Px, they can be transplanted to the seedbed for cultivation.

Grafting surface: Select a “Liangtianchi” (dragon fruit rootstock) that grows well, has plump stem flesh, and is free of pests and diseases as the rootstock. Graft on a sunny day. First use a knife to cut the dragon fruit stem into a flat surface, then insert the scion, align the cambium, and tie it firmly with cotton thread. Generally, at 28-30°C, in about 4-5 days, a large amount of callus tissue will form on the wound junction. If the color of the scion is similar to the color of the rootstock, it indicates that their vascular bundles have healed and the grafting has succeeded. After that, they can be moved into a temporary planting seedbed to continue cultivation.

5. Pest and disease control

Red spot: For fruit trees with relatively severe disease, before they sprout, spray 0.3-0.5{bf} ferrous sulfate solution, or a mixed solution of 0.5 jin copper sulfate, ferrous sulfate and 1.25 jin quicklime with 160 jin water, to control the occurrence of the disease; you can also inject 0.05-0.1{bf} ferrous sulfate solution or 0.05-0.1{bf} ferric citrate solution into the trunk, which has a good effect; you can also apply chelated iron to the soil to improve the soil condition, or spray 0.1-0.2{bf} chelated iron solution on the leaf surface to restore the leaves to green. However, when applying to the soil or spraying on the leaves, the amount of the agent must be controlled to avoid excessive use and causing phytotoxicity.

Rot disease: It is generally caused by insect wounds, or by mechanical injury followed by long periods of rainy weather. You can use a knife to cut off the diseased part, or cut open and drain the rotted tissue during sunny high temperatures, allowing the injured part to dry naturally, or apply an appropriate amount of sulfur-phosphorus powder for control.

Generally, facility cultivation has relatively high humidity, which easily causes plants to suffer from sooty mold. During cultivation, ventilation should be strengthened, and the affected areas should be washed with clean water. In winter, the climate in the greenhouse is relatively dry, and plants are prone to red spiders. Therefore, the humidity in the greenhouse should be kept suitable. If the insect population density is relatively high, omethoate can be diluted and sprayed for control.