Is dry land suitable for growing Sichuan pepper trees? Which varieties are good to plant? When to plant? How to plant?

Sichuan pepper, also known as dajiao, Qin pepper, and Shu pepper, is a tree commonly found in most parts of our country. Because of its high edible value and medicinal value, it is widely cultivated. At present, it is grown in most parts of our country, so is dry land suitable for growing Sichuan pepper trees? Which varieties are good to plant? When to plant? How to plant?

Dry land is suitable for growing Sichuan pepper trees, because Sichuan pepper is drought-tolerant and likes sunlight, and can be planted on plains or in mountainous areas at higher altitudes.

Suitable varieties to plant:

1. Large-type Sichuan pepper: dajiao, Shizitou, Dahongpao, Zhenglujiao, Wawajiao;

2. Small-type Sichuan pepper: xiaojiao, xiaohongjiao, xiaohuangjin, Maojiao, Doujiao, Huojiao, etc.;

3. Other Sichuan peppers: Qiuzajiao, Baishajiao, Gaojiaohuang, Goujiao, Choujiao, etc.

Planting time:

The conventional sowing time is from the end of September to early October, and either broadcasting or drilling can be used. After sowing, cover with fine river sand with a particle size of 1-2mm or cover with wheat straw, preferably so that the soil is not visible, to help preserve moisture, prevent crusting, and improve the seedling emergence rate; in addition, growers have also explored a method in which the fruit is harvested, dried in the shade, and sown immediately the same day. This method no longer requires seed treatment, and the seedling emergence rate is also relatively high.

Planting techniques:

1. Selection of seedling-raising land

Sichuan pepper seedling-raising land should be selected in a place with fertile soil, good drainage, and convenient transportation. To improve the quality of seedlings for afforestation, it is best to choose a site near the planned plantation area. This not only reduces the cost of seedling transport, but also ensures seedling quality and reduces the time from lifting seedlings to planting, thereby increasing the planting survival rate.

2. Seed collection

For seed collection, choose Sichuan pepper trees that are in full fruiting stage with good varieties, vigorous tree growth, and high yield.

3. Seed treatment

Sichuan pepper seeds have a waxy layer on the outer shell and are difficult to germinate in the same year. During seedling raising, the wax must be removed before the seeds can absorb water and germinate. The seeds can be soaked in a 3%-5% edible sodium carbonate solution for 3-4h, then rubbed and washed with fine sand with a particle size of 2-3mm to directly remove the wax. Fresh cow or sheep manure mixed and piled for decomposition, or soaking in laundry detergent solution, can also be used to remove the wax.

4. Thinning and final spacing of seedlings

When the seedlings grow to 4-5cm, thin them; when the seedlings are about 10cm tall, set the final spacing. Thinning and final spacing should strictly follow the principle of “keep the strong and remove the weak, keep the tall and remove the short, keep the healthy and remove the diseased”, and can be carried out together with loosening the soil and weeding.

Sichuan pepper planting methods

1. Planting time

Sichuan pepper trees can be planted in two seasons, spring and autumn, but planting around the Spring Equinox in spring is better. Spring planting should be carried out before the seedlings sprout. When planting pepper seedlings in autumn, part of the tender shoots and tender leaves should be removed to reduce water evaporation and improve the survival rate.

2. Seedling selection

When establishing a Sichuan pepper plantation in mountainous areas, 2-year-old seedlings should be selected, preferably dryland seedlings, with a ground diameter of about 1cm. The root system must be complete. There are no strict requirements for plant height, but there must be no rotten branches or leaves and no pests or diseases. Varieties can include Dahongpao, Dahongjiao, Xiaohongjiao, Baishajiao, Doujiao, Qin'an No. 1, and other local excellent varieties.

3. Planting density

Sichuan pepper planting must avoid close planting. Generally, 4m×6m or 6m×6m is suitable. To improve land utilization and increase income, crops such as peanuts, codonopsis, vegetables, and potatoes can be intercropped in the early stage of plantation establishment.

4. Planting method

When planting Sichuan pepper, seedlings should be planted as soon as possible after being lifted. Spring planting must be carried out before the seedlings sprout. If transport is needed, the roots of the seedlings should be placed in plastic bags (the whole plant must not be placed in plastic bags). When planting, dig large holes and apply sufficient base fertilizer. Generally, the planting hole is 50-60cm3, and each hole is given 3-5kg of farmyard manure and 50g of superphosphate. The fertilizer should be mixed evenly with the soil, and 100g of fresh lime powder should be added to prevent root rot. When planting, use the method of “one bury, two press, three lift the seedling”. After planting, water to settle the roots, and after the water has fully infiltrated, cover with dry soil to preserve moisture.

Field later-stage management techniques

1. Fertilization

For young trees, a small amount of phosphate fertilizer can be applied at planting to promote root growth. After that, a small amount of urea can be applied each year together with loosening the soil. When controlling pests and diseases, potassium dihydrogen phosphate can be used for foliar topdressing. After entering the full fruiting stage, each year after the fruit is harvested, open a ring-shaped trench below the outer edge of the treetop and mix organic fertilizer and compound fertilizer. Apply about 0.25kg of compound fertilizer and about 15kg of organic fertilizer per tree, which can ensure the tree's nutrient consumption.

2. Winter management

Sichuan pepper trees have relatively weak cold resistance, so attention must be paid to winter climate changes, and overwintering management of the pepper trees must be done well to ensure normal growth of the pepper trees.

For young Sichuan pepper seedlings, methods such as wrapping with straw or pressing and burying can be used. That is, before winter begins, wrap the trunk with wheat straw or straw bags, and bind and tie the outside with plastic film to avoid freezing damage; or pile soil beside the roots, then slowly bend the whole tree down and cover it with about 20cm of soil, and promptly remove the warming measures before the seedlings sprout in spring. For larger pepper trees, methods such as whitewashing, watering, and spraying plant ash liquid can be used to prevent freezing damage.

In recent years, late frost has been common in Gangu County, causing huge losses to the growth and fruiting of Sichuan pepper trees. In response to this natural phenomenon, weather forecasts should be listened to in time, and the method of lighting piles for smoke can be adopted to recover losses. Generally, 75-90 piles of semi-wet firewood and grass per hm2 are sufficient. Light them after 12 o'clock at night, and someone should watch over them and pay attention to fire prevention.

3. Flower preservation and fruiting

During the flowering period, Sichuan pepper trees must not be sprayed with dimethoate emulsifiable concentrate, otherwise fruit drop will be very serious. Potassium dihydrogen phosphate plus urea water solution can be sprayed during the flowering period to prevent flower and fruit drop. At full bloom, spray gibberellin 10mg/kg on the leaves; at full bloom and mid-bloom, spray 0.3% potassium dihydrogen phosphate plus 0.5% urea water solution; after flowering, spray 0.3% potassium dihydrogen phosphate plus 0.7% urea water solution every 10 days.

Pruning can be carried out together with fruit harvesting, or from late autumn onward during the dormant period.

4. Pruning methods

In the year young trees are planted, at about 30cm above the ground, choose a plump bud and cut off the trunk above it. Afterward, among the branches sent out from the base, keep three or four branches with uniform and staggered angles according to direction and cultivate them as main branches, removing the remaining branches. On the main branches, cultivate side branches year by year. On each main branch, 5-8 side branches can be cultivated according to the tree's growth condition, and on the side branches, three or four groups of fruiting branches can be cultivated. Generally, no upward-growing branches or downward-growing branches are kept on the main branches.

In daily management and care, diseased and pest-damaged branches, overlapping branches, and sprouting branches should be removed in time. For water sprouts, they can be left unpruned; those that can be used by bending branches should be fully utilized, and those that cannot be used should be removed in time to reduce the consumption of water and nutrients.