The Latest Mint Cultivation Techniques: A Detailed Tutorial

Mint, also known as wild mint, is a perennial herbaceous plant that mostly grows by wetlands and rivers in the mountains and wilds, with rhizomes creeping underground. The whole plant has a fresh, fragrant aroma, with opposite leaves, small pale purple flowers in a lipped shape, and after flowering it produces small dark purple-brown seeds. Mint prefers warm, humid environments with plenty of sunlight and abundant rainfall. It is produced in all parts of the north and south, growing in moist places beside water, at altitudes up to 3500 m. Mint is one of the commonly used traditional Chinese medicines; it is a pungent, cooling diaphoretic and antipyretic drug, used to treat influenza, headache, red eyes, fever, sore throat, and swollen and painful gums. For external use, it can treat neuralgia, skin itching, rashes, and eczema.

Seedling Raising

1. Rhizome propagation: Cultivate seed roots in late April or late August. In the field, select healthy, pest- and disease-free plants as mother plants, and plant them at a spacing of 20×10cm. After harvesting the aboveground stems and leaves in early winter, leave the rhizomes in place as seed plants.

2. Division propagation: When mint seedlings are about 15cm tall, thin and fill in the seedlings. Use the thinned seedlings for division and transplanting.

3. Cutting propagation: In May-June, cut the aboveground stems and branches into 10cm-long cuttings, and insert them into a prepared seedbed at a row spacing of 7×3cm for rooting and seedling cultivation. After rooting and sprouting, transplant them to the field for cultivation.

Transplanting

1. Transplant mint in early spring of the second year before it has sprouted. Early planting leads to early sprouting, a longer growth period, and higher yield. When planting, dig up the rhizomes, select thick, short-jointed, disease-free rhizomes as seed roots, cut them into 7-10cm-long sections, and then open 10cm-deep furrows on the prepared bed at a row spacing of 25cm. Place the seed roots diagonally in the furrows at a plant spacing of 10cm, cover with fine soil, firm the soil by stepping on it, and water.

2. Pinching and topping: In May, when the plants are growing vigorously, promptly remove the terminal buds to promote the growth of side branches, stems, and leaves, which helps increase yield.

First-Cut Period Management (from emergence to the first harvest)

1. Check seedlings and replant: After the field has basically full stands, check the seedlings promptly, and replant missing or sparse spots and patches.

2. Cultivation and weeding: After full emergence, cultivate and weed between rows and weed manually between plants to preserve soil moisture, increase (soil) temperature, eliminate weeds, and promote seedling growth. Cultivate and weed 2-3 times before row closure. Before harvest, pull out all weeds in the field to prevent the odor of other weeds from affecting the quality of mint oil.

3. Timely topdressing: When seedlings are 10-15cm tall, open furrows and apply topdressing, applying 10kg of urea per mu. After row closure, spray twice per mu with 5ml of Pen Shi Bao + 150g of potassium dihydrogen phosphate + 150g of urea.

4. Scientific watering: Mint needs more water in the early and middle stages, especially in the early growth stage when the root system has not yet formed and requires more water. Generally, water about once every 15 days, and water 4-5 times from emergence to harvest. After row closure, water lightly and appropriately to avoid excessive stem and leaf growth, lodging, and shedding of lower leaves, which reduces yield. Stop watering 20-25 days before harvest. At harvest time, it is best when the ground looks “pale”.

5. Disease control

① Black shank disease, occurring at the seedling stage, with symptoms of shrinkage and sunken stem base, blackening, rotting, and plant lodging and wilting. For control, during the disease period, use 100-150g of 70% chlorothalonil or 40% carbendazim per mu, diluted with water and sprayed.

② Mint rust, prone to occur from May to July, spray leaves with a 1000-1500 times dilution of 25% triadimefon.

③ Leaf spot disease, occurring from May to October. In the early stage of the disease, spray a 500 times dilution of 65% zineb once a week to bring it under control.

6. Pest control

The main pest of mint is the “looper”, with damage periods around mid-June and late August. Generally, when the pest density reaches 10 insects/m2, use 15-20ml of Decis per mu and spray 1-2 times, or spray with a 1000 times dilution of 80% dichlorvos.

7. Timely harvesting

In early July, when 10-30% of the flower buds on the main stems of mint are in full bloom, begin harvesting. When harvesting, cut the upper stems and leaves evenly near the ground. The cut mint should be spread out immediately to dry and must not be piled up, to avoid fermentation. Harvesting mint too early reduces the oil yield; harvesting too late increases the furan content in the mint, affecting the quality of the oil. Bundle the wilted mint promptly for distillation and oil extraction.

Second-Cut Period Management (from after the first harvest to before the second harvest)

1. The second-cut period of mint has a relatively short growth period. After the first cut harvest, promptly and quickly sweep up fallen leaves for distillation and oil extraction. Remove residual stubble, weeds, and creeping stems from the ground as soon as possible (generally to a depth of 2-3cm) to encourage young shoots of the second-cut seedlings to emerge from the rhizomes.

2. After hoeing the residual stubble, water immediately to promote early and rapid growth of the second-cut seedlings, extend the growth time, and increase yield. During the second-cut period, water 3-4 times. When seedlings are 10-15cm tall, broadcast (in furrows) 10kg of urea per mu, apply foliar topdressing 1-2 times, and pull large weeds 1-2 times before harvest, ensuring no weeds remain in the field before harvest.

Harvest

1. The harvest time is from mid-September to mid-October.

2. When dried to 70-80% dryness, tie into small bundles, then dry until completely dry. The best quality is dry with full leaves, dark green leaf color, purple-brown or light green stems, and a rich aroma.