The Benefits of Sweet Potato Leaves, a Summer Vegetable, and Efficient Fertilization Methods

Hailed as a “longevity food,” sweet potato is rich in protein, starch, pectin, vitamins and various minerals. As a crop frequently grown by farmers, sweet potato has a relatively wide planting area; therefore, during cultivation, everyone needs to pay attention to scientific fertilization for sweet potato. So what are the benefits and effects of sweet potato leaves? And how should sweet potato be fertilized to achieve high yield?

I. The Best Time to Fertilize Sweet Potato

The tuber-promoting fertilizer is generally applied about 45 days after transplanting the vines, when the aboveground part has already spread its vines down the ridges and the tubers have basically taken shape; on one side of the ridge, break open 1/3 with a plow and then apply the fertilizer immediately. Breaking the ridge to fertilize can improve soil aeration and is beneficial for tuber expansion. This fertilization is mainly potassium fertilizer; applying potassium fertilizer as a top dressing can thicken the stems and leaf stalks, keep them in a tender state, and promote tuber expansion.

Generally, late July to early September each year is the period of sweet potato storage root expansion. This period is also the key period for yield formation and the period of greatest fertilizer demand, so attention should also be paid to topdressing sweet potato during this time.

II. High-Yield Fertilization Methods for Sweet Potato

1. Apply crack fertilizer heavily.

“Crack fertilizer” is very important for improving sweet potato yield and quality. When cracks appear in the ground in the early expansion stage, irrigating with crack fertilizer can prompt nutrients to continue moving to the roots, promote storage root expansion, and achieve the goal of increasing yield. You can use 3%-5% potassium sulfate, 15%-20% wood ash extract, or 1% monopotassium phosphate fertilizer solution, 150-200 kg per mu. If the sweet potato growth is weak, urea can be appropriately added, about 5 kg.

Preparation of wood ash water: use 10 kg of wood ash, add 50 kg of water, soak for 4 hours, and take the clear filtrate. When applying crack fertilizer, it can be done together with irrigation through drip tubes or sprinkler irrigation. Those without drip tubes and fertilization facilities can also fill the cracks manually, but because the efficiency is too low, few people use this now. Flood irrigation can also be used to apply the fertilizer with the water, but the irrigation amount must be controlled; too much or too little will both give poor results. When applying with water, the fertilizer must be fully diluted to prevent fertilizer concentration from causing fertilizer damage.

2. Skillfully supplement foliar fertilizer.

In the late expansion stage of sweet potato, as fertilizer demand increases and the sweet potato root system gradually ages, the root absorption capacity weakens, and fertilizer deficiency is likely to occur. Plots showing fertilizer deficiency can be supplemented in time through foliar topdressing, extending the leaf photosynthesis time, preventing premature aging, and improving sweet potato yield and quality. Per 667 sq m can be used. Foliar topdressing in the late expansion stage has a very obvious effect on improving sweet potato yield and quality, and this work must not be neglected.

III. Benefits and Effects of Sweet Potato Leaves

1. Enhance immunity

Sweet potato stem tips contain abundant mucilaginous protein, and sweet potato leaves contain 5-10 times more antioxidants than ordinary vegetables, which can improve immunity and prevent colds.

2. Help detoxify

Sweet potato leaves are rich in chlorophyll, which can purify the blood and help detoxify.

3. Prevent high blood pressure

Sweet potato leaves are rich in potassium, which can maintain the balance of osmotic pressure inside the body and help control blood pressure.

4. Prevent anemia

Consuming 300 g of sweet potato leaves daily can supplement the iron and vitamins A, C, and E needed by the human body for one day.

5. Improve constipation

Sweet potato leaves are rich in dietary fiber, which can promote gastrointestinal motility and thereby prevent problems such as “constipation and hemorrhoids.”

6. May fight cancer

Sweet potato leaves are rich in polyphenols, and polyphenols have antioxidant functions. Oxidative damage is an important cause of many chronic diseases, such as cardiovascular disease, cancer, and aging. Therefore, the antioxidant function of polyphenols can play a preventive role against these chronic diseases.

7. Promote milk secretion

Sweet potato leaves contain substances such as flavonoids, which can promote milk secretion.

8. Improve eyesight

Sweet potato leaves are rich in vitamin A, so they have a very good effect on improving eyesight.

9. Improve menopausal symptoms

Sweet potato leaves are rich in phytosterols, which can achieve effects similar to hormones in regulating body functions, thereby improving menopause.