How to plant red dragon fruit? How to achieve a balance between cost and yield through planting techniques

Honglongguo, originally grown in tropical rain forests, began to be planted on a large scale in Taiwan in the 1980s. It has been familiar to Taiwan in recent years and is a new darling in the vegetable and fruit market. Starting from raising seedlings, the following will describe the planting techniques of red dragon fruit respectively, as a reference for farmers when planting red dragon fruit.

Cuttings are the most common in raising and planting seedlings.

In the early stage, because the branches were not easy to be obtained, they could only be planted by mass propagation of seedlings. At present, the propagation of cuttings was the most common, and the branches were cut off and planted directly in the field. The branches of the red dragon fruit have aerial roots, which can take root after 1-2 months of planting. For seedling raising, the length of cuttings should be more than 30 cm, and succulent stems with strong growth, sturdy, sunny, pest-free and 1-2 years old should be selected, sharpened or diagonally cut at the base, placed in the shade to allow the wound to dry and heal, stained with a little rooting agent or plus fungicides, and then obliquely inserted into the loose culture soil to speed up the rooting rate and reduce the decay of the incision. If you can scrape off a little fleshy stem to expose the central vascular bundle cutting is better.

Whether the cultivation technique of red dragon fruit is good or not will be directly reflected in the appearance. This is the Vietnamese red dragon fruit, that is, the color is not good in appearance, the pericarp can not turn red completely, and the scales are long and thick.

The cut fleshy stem can be dried in the shade for several days, and then cut after the wound heals, which can prevent the base rot (basal rot). The cut branches can also be planted directly, but the depth should not exceed 3 cm, and the soil should be covered around the base. The initial water supply should not be too much, otherwise the wound is easy to rot, but after 2 months of growing roots, the water supply should be sufficient to speed up the emergence of new buds. At present, cutting propagation is the most rapid and simple method of seedling cultivation, and it can retain the characteristics of the original mother plant, and can be carried out all the year round.

When updating varieties, grafting is generally used (including cutting, tender shoot grafting, bud grafting, embedded grafting, etc.). If we choose the appropriate grafting method according to the climatic environment and branch growth, the survival rate can be more than 80%. When cutting or mosaic propagation, the rootstock is perennial, the fleshy branch without bud is the best, the rootstock is at least 30 cm long, and the grafting at high temperature must be protected by paper bag to prevent scion from losing water and withering; tender shoot grafting and bud grafting are mostly carried out in the cooler climate in early spring, and if the bud grows to more than 90 cm after grafting, it can blossom every other year when the climate is suitable.

Red dragon fruit is suitable for planting all the year round, but the cooler seasons in spring and autumn are the best, which can reduce the loss of water in branches. After planting, the new branches can blossom after 10-14 months, and the original mother plant may sprout in the same year, but the mother plant and too young new branches do not leave flowers and fruits, based on the principle of cultivating robust branches, generally starting to leave a small amount of fruit every other year after planting.

One of the replacement methods for the renewal of red dragon fruit is that the vascular bundles in the center of the panicle anvil should be cut and joined closely.

Support frame, cement material is more durable

Red dragon fruit is a perennial succulent plant, the main branch must be attached to the wall or support frame, so that it can grow, interested growers can plant next to fences, fences and other supports, large-scale commercial cultivation must build climbing facilities, and must take into account firmness and durability. As the type of support frame affects the convenience of future management operations, including pruning, bagging and harvesting operations, as well as the production capacity per unit area and the cost of lighting treatment, it is necessary to carefully evaluate in order to reduce production costs.

More than 10 years ago, grape sheds were mostly used for horizontal planting, fence climbing, single plant laissez-faire planting, erection of plastic pipes and other production models, but most of the above-mentioned methods have been eliminated. The commercial production mostly adopts the following two ways to set up the frame, and the row spacing varies according to the type of support, the general row spacing is 2.8 to 3.2 meters, the plant distance to a single pile is 2 to 2.5 meters, the A shape is 45 to 60 centimeters, and the height of the support frame is 1.2 to 1.8 meters.

I. single pile type or iron tower type

This method is mostly used in Central America and Vietnam, and the erection materials include cement columns, corrosion-resistant tree trunks, pouring cement into plastic pipes, pipe pipes or combination of anti-rust iron strips, slub steel, and so on. This method is convenient for management and operation, and it can also be cultivated in 2-3 layers (pillar height is high), which can increase the yield. In the case of a cement column (with a total length of about 180,210 cm), it can be designed and erected with a depth of about 60 cm, a height of 120 cm to 150 cm, a diameter of 10 cm and a diameter of 10 cm. The column contains two 4-inch steel bars and is mainly square in shape. Although its construction cost is expensive, it is durable for a long time, and its load-carrying capacity is better, so it is the longest-lasting material in a single column. (see Table 1)

Planting method is to choose to plant 2 ~ 3 seedlings on the four sides of the column, first tie and fix them artificially with plastic ropes (cloth strips), and then fix them on the cylinder after the aerial roots grow out in the future, so that the branches climb to the top along the column, and after elongation, they are attached to the iron ring and then move around to make them spread and droop, only the drooping branches let it bud and blossom, and the lateral buds of the trunk are all cut off. Because occasional branches will break from the top of the cement column, in order to avoid this situation, the rings such as waste tires, iron frames or tension cables should be tied with iron wire or supported at the top, so as to avoid excessive temperature or breaking at the attachment site.

The use of wooden piles for planting is often due to wood decay or overload and lodging of the whole plant, which is not recommended. Single pile planting is independent cultivation, does not need to consider the planting direction, and the ventilation and light transmittance is the best, which can reduce the spread rate of the disease. In branch management, the drooping branches should be evenly distributed around (artificial assistance) to avoid tilting.

The cost of welding round iron frame is low, but the gravity resistance of branches should be considered to prevent lodging.

Type A shelf arrangement

Pipe, galvanized pipe, iron bar, plastic pipe or bamboo pole are cross-framed into an A-shaped shape, the fork point is then horizontally placed or another buried pile tension cable is strengthened to support the growth of the branches, and the growing vines are pulled to the horizontal rack and evenly distributed. this method is still convenient for harvest and management, and the setting cost is slightly lower than that of a single pile cement column.

The branches can make effective use of the space between plants, have more fruiting surfaces, and have the highest yield per unit area, and it is beneficial to the treatment of lamp production and adjustment. However, this method should pay attention to the light intensity of the arrangement (mainly north-south) and the wind surface (to prevent lodging). The disadvantage is that due to intensive cultivation, poor ventilation, complex branch covering, it is not easy to control the number of branches. Manual fruit picking and pruning are easy to be stabbed. Planting methods such as A-shaped shelves are high-density planting, which will spread rapidly once the disease occurs, which is not conducive to the prevention of diseases and insect pests.

III. Other non-large-scale cultivation

The red dragon fruit can be attached to low walls, graceful stones, living tree stumps, and even telephone poles. Scaffolding (using grape shed) is the least suitable as an appendage. in this method, red dragon fruit branches grow like grapevines on the surface of the scaffolding, bud and blossom less because of more branches to the horizontal extension of the stem, and most of the fruit surface is difficult to be harvested on the scaffolding. Many years later, the branches on the top of the shed are also difficult to renew and prune. The natural drooping branches are easier to blossom and bear fruit. Although the horizontal branches are exposed to more light, they are easy to sprout new buds, but the amount of fruit is low.

Removing buds, picking hearts, weeding

Every spring, the thorns on the branches are easy to produce new buds, and the buds (thorns) on the trunk and the main branches should be completely cut off with a banana knife. if it is the fruiting mother branch, 1 or 2 buds can be selected and cultured in the upper position to form the fruiting branch. When the fruiting branch reaches more than 60-90 cm, it should be coring or truncated, so as to avoid further growth touching the ground or furrow, and promote the branch to mature and blossom and bear fruit earlier.

Because the root system of Honglongguo is shallow and has fleshy stems, do not use systematic herbicides such as spring every year to control weeds. Instead, we should use mechanical weeding or covering rice husks and mat to control weeds. In addition, grass cultivation can conserve water and fertilizer, increase soil temperature, prevent soil erosion and reduce soil nutrient loss, which is helpful to the growth of red dragon fruit root group, but some diseases and insect pests may increase. For example, ants, stink bugs and snails should pay more attention to prevention.

The use of machinery for shredding branches is beneficial to the removal of field branches.

Pruning: necessary work to control the number of branches

In the budding stage, the red dragon fruit is often worried about the collapse of the support because the fleshy stem grows too luxuriantly, so pruning is a necessary task to control the number of branches every year. The way of pruning will affect the difficulty of pruning and indirectly affect the cost of manpower management, so the height of the pillar should be considered at that time to facilitate pruning.

The annual pruning is roughly carried out after the end of the production period, first of all, the branches of the current year are thinned and deleted, and then combined with irrigation and fertilizer cultivation to promote the sprouting of new branches, and then choose to cultivate this new branch as the fruit branch next year. In addition, the overall nutritional status of the plant should be taken into account in pruning.

The branches of the red dragon fruit are divided into three kinds according to the year. The first is the "3-year-old branch", which can no longer blossom because all the bud eyes have flowered or sprouted. In order to avoid the pillar bearing overweight, the old fruiting branches are cut off from the base every year after harvest to re-cultivate new fruiting branches. In addition, "1-2-year branches" are the easiest to blossom and bear fruit, and the selection criteria vary with different varieties; because the production period of red meat species ends later, new branches begin to sprout in December of the same year, and this kind of new branches have the ability to bear fruit only after more than 5-6 months, so the immature branches of the year before last had better leave no fruit or leave fruit at the end of the year. Due to the early end of the production period, the white meat species began to sprout new branches in October, and at this time they can begin to cultivate the new branches as fruit branches in the next year.

In order to control the quality of red dragon fruit, it is recommended that there should be no more than 2 buds on the same branch, and the whole plant should be controlled below 20 flowers.

Control quality: flower thinning, pollination, fruit thinning

The red dragon fruit can bloom more than 10 batches a year, and 4-6 batches of flowers and fruits are mostly selected for commercial cultivation, but it is difficult to control the fruit quality if the fruit is left in each batch. In order to produce large and high quality fruit, we must do a good job of flower thinning, bud thinning and pollination.

Flower thinning begins with flower bud thinning, and the number of buds on the same branch should not exceed 2. After the bud grows into a bud or the fruit is determined, it can be thinned again. Generally speaking, bud thinning can be carried out 3 days after budding, mainly to remove poor growth, contiguous and abnormal buds. There are about 6-8 buds in the branches of the same main branch, and each batch of flowers and fruits of the whole plant should be controlled below 20 flowers (fruits), and each branch should also leave fruit in batches. After the flower fade, remove the deformed fruit and sick and weak fruit in time, leaving at most 2 fruits per branch.

At present, most of the cultivated species no longer need artificial pollination, but there are still some red flesh species. Because of the difference in floral structure or self-flowering incompatibility, artificial or cross-pollination is still necessary to ensure fruit shape hypertrophy and yield increase. Pollination actually only needs to stick the pollen on the stigma, and there is no need to pour the pollen into the hole of the style. Because the red dragon fruit flower is large, it is said to be simple and easy compared with other fruit trees.

The effective pollination time may be from 6 p.m. to 7 a.m. the next morning, but it is best when the flowers are in full bloom from 8 p.m. to 12 p.m. If they encounter heavy rain (the degree to which the petals can be broken) within 4 hours after pollination, most of the flowers will not bear fruit. Pollination should be light, using a brush to get pollen and gently touch the stigma. The pollen is collected in the afternoon and will bloom on the same day, or pre-stored in the refrigerator freezer. It still has germination power after 1 week. In order to avoid only blooming but not bearing fruit, 10% other different varieties and lines can be planted to increase the degree of pollen differentiation in the orchard and reduce the phenomenon of self-flowering incompatibility. In addition, the pollen tube did not reach the ovary ovule 18 hours after pollination, and it took at least 48 hours to pollinate the red dragon fruit, so the style should not be removed 3 days after anthesis.

After pollination, the ovary was enlarged and enriched day by day, but because of its large floral organ and no obvious detached tissue between ovary and style, the withered petals were not easy to fall off by themselves. In order to prevent the withered petals from becoming a hotbed of bacteria, the petals should be removed within 7 days after pollination. After the end of the natural fruit drop period, the fruit on the weak vine should be cut off, the weak fruit and abnormal fruit should be removed, and the branches with too many fruits should be artificially thinned. In principle, one fruit should be left on the same fruiting branch about 30 cm, so as to prevent the fruit from becoming smaller due to nutrient competition.

Gauze net is another special bagging material, which not only has the characteristics of good air permeability, but also can prevent and control bird damage and oriental fruit flies.

Bagging: reducing human injury caused by insect pests

The early cultivation of red dragon fruit is not used to bagging, but in recent years, it has been found that bagging can reduce fruit fly, snail, bird damage, skin sunburn and man-made damage, and can improve the brightness and cleanliness of the pericarp, and the coloring is more uniform, which helps to improve the commodity value and increase the market price.

The bagging time is usually started after Xiehua and completed within 2 weeks. In the early days, waste newspapers were used in fruit bags, but in recent years, various materials such as black screen, green screen, white paper bags, non-woven bags, plastic cup covers and thin Kraft paper bags have been used. The results showed that the kinds of materials suitable for different climatic conditions were different. In central Taiwan, the effect of non-woven bags and thin Kraft paper bags was the best, and the coloring was the most uniform and did not affect the fruit quality.

Because of the high temperature in southern Taiwan, the effect of the gauze with good air permeability is better. The shading rate of non-woven bags and thin Kraft paper bags is good, but the air permeability is poor. When used at high temperature, the fruit ripening will be accelerated, the quality will become worse, and the soot disease is serious. In the process of bagging management, attention should be paid to the smooth discharge of stagnant water at the bottom of the bag, so as not to cause excessive moisture in the bag and increase diseases and insect pests.