What methods are there to improve the survival rate of sweet persimmon plantings?

How can the survival rate of sweet persimmon plantings be improved?

1. Use large, strong seedlings

Persimmon trees with thick, sturdy seedlings and well-developed root systems have ample nutrient reserves within their bodies and strong resistance. Not only is the planting survival rate high, but after planting they also sprout early, grow long shoots, their ground diameter thickens quickly, and they take shape quickly. Generally, by the third year after planting they already produce a certain economic yield (Figure 1). Those slender seedlings and seedlings lacking fine roots generally sprout later and produce short, few shoots. According to our observations, for the above two types of seedlings planted in spring, the sprouting time is mostly after late May, and in a few cases the sprouting time is even in late July, with the length of shoots by leaf fall being less than 6 cm.

Figure 1: Fruiting condition in the third year of an orchard established with large seedlings (location: Gongyi City)

In addition, the seedlings selected should as far as possible have complete root systems without major damage, because wounds are extremely difficult to heal under the interference of tannin substances, which reduces the survival rate.

2. Advocate planting nearby with soil attached, and strictly prohibit leaving roots exposed for too long

Because the root system of persimmon trees contains tannin substances, when exposed to air for too long it easily causes the fine roots to brown and die, making it difficult to grow new roots after planting and reducing the survival rate. To solve this problem, the author advocates carrying out planting nearby with soil attached close to the seedling nursery, where the survival rate is almost 100 percent (Figure 2). For those who need to purchase seedlings from far away, after lifting the seedlings they should be dipped in mud slurry in a timely manner and the root systems wrapped and protected with binding material (woven bags), then planted immediately upon arriving at the planting site. Seedlings that cannot be planted should be heeled in by deep burying the roots in moist soil, and it is strictly prohibited to use the heeling-in method of regularly sprinkling water onto the roots of persimmon trees.

Figure 2: Selecting high-quality large seedlings and transplanting them nearby with soil attached (location: Gongyi City)

3. Advocate early autumn and late spring planting

Because the root activity of persimmon trees has particular characteristics, with root activity stopping early in autumn and starting late in spring, the planting time for persimmon trees should be in early autumn and late spring. The author's practice is: for autumn planting, when the leaves of the persimmon tree begin to show leaf fall, lift and plant the seedlings; for spring planting, the best time is generally when the persimmon buds are about to break dormancy. If planting is done after the persimmon buds swell and show green, the survival rate will be reduced on dry ridge land [Jishan Huayao].

4. Scientifically water the settling water well and lay the moisture-preserving film well

Because the root system of persimmon trees has low osmotic pressure, the roots of newly planted trees have poor water-holding capacity. If the soil moisture is insufficient, it is very easy to cause the persimmon tree roots to lose water, so the settling water should be watered scientifically. The method is: immediately after planting, water thoroughly once, then water again after 4-5 days. After the water seeps down, straighten the seedling and fill soil to 3 cm below the graft union, then lay a piece of white plastic film 80 cm square under the tree basin, and firm it with soil around the edges and at the root collar of the fruit tree, which can achieve the effect of increasing temperature and preserving moisture (Figure 3).

Figure 3: Covering the tree basin with plastic film and firming it with soil can preserve moisture and prevent weeds (location: Xinzheng City)

If the soil moisture is found to be insufficient before sprouting, water once more.

5. Advocate low trunk heading, and wrapping the trunk with plastic film or covering it with a thin film bag

Because the root activity of persimmon trees is later than that of the aboveground part, when spring arrives the aboveground part will preferentially begin activity, and plump buds will swell. When underground water supply cannot keep up, it often leads to "bud withering." Therefore, in order to reduce the loss of tree nutrients in spring, the author advocates heading at the sub-plump bud zone below 60 cm to delay the sprouting time of the aboveground part, and after heading, wrapping the trunk with thin plastic film or covering it with a thin film bag to reduce water loss. Note: the single layer of plastic film wrapped around the trunk must be pressed tightly against the trunk, especially at the buds, to facilitate later sprouting (Figure 4).

Figure 4: Wrapping the trunk with a single layer of plastic film, which must be pressed tightly against the buds to facilitate sprouting (location: Xinzheng City)