Water Spinach Planting Methods and Timing Explained in Detail

Water spinach (Ipomoea aquatica) originated in the tropical rainy regions of China and is suited to growing in moist areas. It is mainly distributed in the Lingnan region and is a leafy green vegetable commonly cultivated in summer and autumn. Below, we explain in detail the planting methods and timing for water spinach.

I. Planting time for water spinach

1. Open-field planting of water spinach

For open-field planting of water spinach, sowing can generally begin from April to July, and it must be possible to harvest before Frost's Descent (Shuangjiang). Water spinach likes high temperatures and high humidity, prefers moist soil, and enjoys ample light. It is not strict about soil conditions and likes fertilizer and water, so gardeners in the north who want to grow water spinach outdoors must make sure to get the season right.

2. Greenhouse planting of water spinach

Greenhouse cultivation can basically achieve year-round production and year-round supply. In order to obtain relatively high economic returns, sowing should be arranged from October to December, with harvest from December to March of the following year.

II. Planting methods for water spinach

1. Management after sowing with a seeder

(1) Sowing

For direct sowing, first soak the seeds to promote germination, then sow in holes at a row spacing of 35 cm and a hole spacing of 15-18 cm, with 3-5 seeds per hole and a seeding rate of 2.5-3.0 kg per mu. For raising seedlings and transplanting, you can combine thinning of the seedlings for market, using the method of broadcasting in a seedling bed and thinning the seedlings. After sowing, cover the seeds with 1 cm of soil. For each mu of planting field, a seedling bed area of 50-60 sq m is needed, with a seeding rate of about 2.0 kg.

(2) Management after sowing

After sowing, preserve soil moisture and keep warm. After emergence, when the seedlings are 3 cm tall, strengthen fertilizer and water management, applying urea with irrigation water at about 5 kg per mu. During the seedling stage, avoid drought. When the seedlings have 2 true leaves and 1 heart leaf, thin them to a spacing of about 6 cm. During the growth period, spray with a 20 mg/L gibberellin solution or Yunda-120 (10 mg mixed with 30 L water), spraying once every 10 days for 2 consecutive sprays. Transplant the seedlings to the planting field when they have 4-5 leaves.

2. Field planting of water spinach

(1) Fertilizing and land preparation

Choose high-quality, fertile sandy loam soil. Apply about 4 cubic m of decomposed organic fertilizer and 50 kg of diammonium phosphate per mu. After plowing and raking finely, make beds with a bed width of 1.0-1.2 m.

(2) Field planting

For all direct-sown plots, open holes and sow at a plant and row spacing of (15-18) cm x 35 cm. For all seedling-raised plots, about 30 days after sowing, when the seedlings are 17-20 cm tall, transplant at a row and plant spacing of 30 cm x 35 cm with 3-4 plants per hole, or transplant at a plant and row spacing of 18 cm x 35 cm with 2 plants per hole. When transplanting, first water the seedling bed, then transplant with a soil ball to help the seedlings recover.

3. Field management

(1) Fertilizer and water management

When water spinach has 2 true leaves and 1 heart leaf or after field planting, strengthen fertilizer and water management, applying about 10 kg of quick-acting nitrogen fertilizer per mu. The amount of topdressing should not be too large, and keep the soil moist during plant growth. Begin harvesting when the seedlings are about 30 cm tall. Apply topdressing at every harvest, with a standard of 10-15 kg of urea per mu, to promote the formation and growth of new shoots.

(2) Cultivation and weeding

To prevent the bed surface from crusting and weeds from growing densely, which affects plant growth, when the bed surface turns white, hoe shallowly to promote root development and create a favorable environment for robust plant growth.

(3) Temperature management

During water spinach production, maintain as high a temperature as possible. For greenhouse production, do not ventilate when the temperature does not exceed 35°C, and keep the nighttime minimum temperature above 15°C. To promote the growth of water spinach, during low-temperature periods, add a small arch tunnel inside the solar greenhouse to increase the temperature.

4. Harvesting water spinach

Water spinach is generally harvested by pinching. The first harvest is when the plant is more than 30 cm tall, leaving the lower 9-12 cm and harvesting the tender shoots above it. Afterward, when the new shoots growing from the leaf axils reach 15 cm, begin the second harvest, but leave 2-3 leaves at the lower part to promote more new shoots and ensure a high yield. After the third harvest, leave only 1-2 leaves below each harvested new shoot to prevent too many new shoots from causing premature plant decline. At the same time, thin out excessively numerous and dense branches at the base of the plant to achieve renewal and maintain a reasonable population.