Key Points and Precautions for Off-Season Planting Techniques

AbstractOff-season planting refers to growing plants in a greenhouse by creating a suitable growing environment to promote plant maturity; its quality and yield are not very different from fruits and vegetables grown in the normal season. Off-season vegetable planting can use methods such as high-mountain off-season planting, insulation-facility off-season planting, and shade-net off-season planting.

I. What Is Off-Season Planting

1. Off-season planting refers to varieties grown in a greenhouse using high-tech methods. Off-season planting does not rely on hormones to grow vigorously; it mainly uses greenhouse facilities to raise the room temperature and thereby change the growing environment, prompting plants to enter the maturity season early.

2.  If off-season fruits and vegetables are grown according to national standards, the growing techniques can generally be guaranteed, and their quality and yield are not very different from fruits and vegetables grown in the normal season. Therefore, avoid buying off-season fruits and vegetables that have been ripened or kept fresh with ripening agents or other hormone-type chemicals.

3. Off-season vegetables and fruits are not entirely grown in greenhouses. Off-season planting can be divided into two major types. The first uses the three-dimensional climate resources of mountainous areas to carry out off-season planting of vegetables and fruits in summer and autumn. The second uses the warm microclimate of winter and spring to carry out off-season planting of vegetables and fruits in winter. For example, regions such as Hainan, because they have abundant heat and light resources, are suitable for off-season planting of vegetables and fruits in winter.

II. Methods of Off-Season Vegetable Planting

1. High-mountain off-season planting

(1) In the hot summer and autumn, low-altitude flatland areas are generally unsuitable for growing heat-sensitive vegetables because of high temperatures, while in high-altitude mountainous areas, because the temperature decreases as altitude increases, the climate remains relatively cool, and heat-sensitive vegetables can be grown during this period.

(2) Generally, August to October is the slack season for vegetables, and high-mountain off-season vegetable planting can provide the market with a rich variety of fresh vegetables. Therefore, planting time needs to be arranged reasonably according to the time to market and the growth period of the varieties.

(3) The main types of vegetables suitable for high-mountain off-season planting are: celery, cauliflower, bell pepper, radish, carrot, tomato, Chinese cabbage, cabbage, green beans, etc., suitable for planting in mountainous areas at an altitude of 800 m or more.

2. Insulation-facility off-season planting

(1) For growing cold-sensitive vegetables in the cold season, plastic greenhouses, small plastic arch tunnels, plastic film mulching, and electrically heated hotbeds can be used for planting. Insulation-facility planting is conducive to earlier market supply and late-autumn delayed supply.

(2) The types of vegetables suitable for earlier market supply include: cucumber, edamame, eggplant, sweet pepper, green beans, water spinach, Ceylon spinach, etc., while the types for delayed supply include: cowpea, sweet pepper, green beans, autumn-winter cucumber, late-autumn tomato, etc.

3. Shade-net off-season planting

Shade net is a new type of covering material. Generally, black shade net can be used for planting. Covering vegetables with it can provide shade, wind protection, and rainstorm protection, and increase the humidity of the garden plot. It also helps overcome the harm to vegetables caused by rainstorms, high temperatures, and strong light in summer and autumn, and can increase vegetable varieties in the hot season.