1. Rooting and seedling slowing down period (lasts about 20 days): The potato seedlings are inserted into the soil until they take root and survive. The seedlings on the ground begin to grow new leaves, most of which The stage when seedlings grow axillary buds from the leaf axils. 2. Branching and potato-bearing period (tubes last about 35-70 days, summer potatoes about 25-35 days): The root system develops very rapidly, mainly growing fibrous roots. 3. The period when stems and leaves are in full bloom (spring potatoes last about 65-100 days, summer potatoes about 40-70 days): stems and leaves cover the ground and reach the peak of growth. 4. Stem and leaf decline and potato tuber rapid expansion period (lasts about 30 days): Stem and leaf growth slows down to stagnant growth, and potato tuber begins to expand rapidly.

1. Four stages of sweet potato growth

1. Rooting and slow seedling stage

Rooting and slow seedling stage refers to the period from planting to planting of potato seedlings. The roots of each node survive, the above-ground seedlings begin to grow new leaves, and the seedlings can grow independently. The stage in which most seedlings grow axillary buds from the leaf axils lasts about 20 days. During this period, the main purpose is to check the survival of the sweet potato seedlings and replenish them in time. After planting the seedlings, drip irrigation should be done in time to promote the seedlings to take root and grow new adventitious roots, prevent the seedlings from drying out, and improve the survival rate. In addition, the seedlings should be sprayed after 20 days. It loosens the soil slightly, which is conducive to the growth of the sweet potato root system.

2. Branch tuber stage

In the branch tuber stage, the root system develops very rapidly, mainly growing fibrous roots, with long axillary buds and main spread, and obvious number of leaves. The number of effective potatoes is basically stable, with spring potatoes lasting about 35-70 days and summer potatoes about 25-35 days. During this period, not only do the branches grow and seedlings grow, but the sweet potato roots also begin to form, so they require the most water and fertilizer. After watering is completed, the soil will become relatively compact, which is not conducive to the expansion and continued growth of the sweet potato rhizomes, so it needs to be loosened, which will be more beneficial to growth.

3. The peak period of stems and leaves

The peak period of stems and leaves refers to the period from when the stems and leaves cover the ground to the peak of growth. During this period, the growth of stems and leaves reaches its peak, and the leaf area index reaches its maximum. Although stems and leaves mainly grow during this period, the sweet potato roots also begin to gradually expand. Spring potatoes take about 65-100 days, and summer potatoes take about 40-70 days. The management at this stage is very important. Sometimes the sweet potatoes will grow vigorously, which is not conducive to the growth of the sweet potato rhizomes. Moreover, it is easy to encounter the rainy season at this stage, so the drainage of water is very important at this time.

4. The period when the stems and leaves decline and the potato tubers expand rapidly

The period when the stems and leaves decline and the tubers expand rapidly, that is, the growth of the stems and leaves slows down until they stagnate, and the tubers begin to expand rapidly. This period lasts until the end of harvest, which takes about 30 days. At this time, the fertilizer absorption capacity of the sweet potato roots decreases. It is necessary to adopt the method of fissure fertilization to promote the expansion of the roots and spray 1 potassium sulfate solution or 5 plant ash leaching solution on the leaves to ensure that photosynthesis on the leaves promotes the formation and formation of carbohydrates. Accumulate to achieve high yield.

2. How long is the growth cycle of sweet potatoes?

1. Depending on the planting time of sweet potatoes, their growth cycles are also different. The growth cycle of sweet potatoes in spring is about 160-200 days. , while summer sweet potatoes generally take 110-120 days.

2. The growth cycle of sweet potatoes can be divided into four growth periods according to the growth characteristics of sweet potatoes, namely the rooting and slow seedling period, the branching and potato forming period, the stem and leaf flourishing period, and the stem and leaf declining period. Rapid expansion period. When planting sweet potatoes, management should be carried out according to the characteristics of each growth period to achieve high yields.