The kaki plant is native to China and is now widespread all over the world. The leaves are bright green and glossy in spring and summer, while in autumn they take on shades from yellow to bright red, after their fall the fruits persist on the branches until they mature, giving the plant a nice and decorative appearance. The persimmon is therefore also an ornamental plant suitable for embellishing a garden.
In this context or within a real orchard, organic cultivation is simple, thanks to its rusticity and resistance to pests and diseases. The kaki belongs to the ebenaceae family and is a species with a rather unique floral biology. The common varieties in Italy have almost exclusively female flowers with aborted male stamens, and consequently the fruits develop by parthenocarpy, or without seeds. In these cases they remain astringent until harvest, and only after ripening do they become sweet and take on a bright red color.
In the presence of another variety, the flower is pollinated regularly and the pulp of the fruit in this case contains the seeds, is brown and has a sweet taste already at the time of harvest. There are also non-astringent kakis that remain compact and are called “apple kaki”, but they are not very common in Italy because they are varieties sensitive to winter cold. The persimmon fruit is very nutritious and can be stored for long periods out of the refrigerator.
Suitable climate and terrain
Climate. Persimmon is considered a sub tropical species but there are varieties that adapt to different climates and that can tolerate winter temperatures of various degrees below zero, down to -15 ° C. This species is widespread throughout the peninsula, although in the north young plants can be damaged due to persistent winter humidity. It is not particularly suitable for windy areas, as the branches could break, especially when they are loaded with fruit. The flowering of the persimmon takes place in mid-May and is followed by a drop of fruit.
The ideal terrain. The persimmon plant prefers fertile, fresh and ventilated soils, free from water stagnation which would favor yellowing and defoliation. However, it also adapts to poor soils giving discreet productions, it is a very adaptable fruit tree from this point of view.
How to plant a persimmon tree
Preparation and suitable period.Similarly to what is done for the planting of other fruit species, the soil must also be adequately prepared for the persimmon. The best time for transplanting is autumn-winter, until the beginning of spring, obviously excluding the periods when the earth is frozen or wet and therefore impractical.
The transplant. For the planting of a single plant we can dig a deep and wide hole, approximately 70 x 70 x 70 cm. The roots in fact need a good volume of loose earth around because the species is sensitive to water stagnation that is generated in compact soils. The plant must be inserted into the hole very straight, with the collar just above the surface of the soil. After having brought the earth back into the hole, properly fertilized, it is gently pressed with the feet and finally watered to stimulate rooting.
Fertilization. Even if the persimmon is not particularly demanding in terms of nutrition, a good fertilization of the plant is a must, and must be achieved by mixing compost or ripe manure to the most superficial layers of the earth covering the hole (which must be the same ones that were in surface before excavation). The addition of handfuls of slow-release organic fertilizer such as hornbill or manure in pellets can be positive. In the presence of very clayey soil it is possible to prevent water stagnation by adding zeolite, a mineral of volcanic origin with interesting properties. In this case, the zeolite improves the permeability of the soil by absorbing excess moisture, so it is worth mixing a few kg with the earth covering the hole.
Rootstock. The persimmon is usually grafted on Diospyrus lotus, a species that gives it a certain resistance to cold and drought, a very useful feature in particular when it is grown in northern Italy.
Planting layouts. Given the remarkable development of the plant, in the orchard it is recommended to leave 6-7 meters between the rows of persimmons and 5-6 meters between one plant and another on the row. Slightly shorter distances can be provided with a single row of persimmons alternating with rows of other fruit trees of smaller size, and this is the typical situation of the mixed orchard.
Cultivation in pots
The persimmon can also be grown in pots, but we should expect a reduced development and lower fruit production compared to that of free plants. Periodically we must remember to repot the plant in larger containers to always ensure a lot of soil to the roots, for a good cultivation it is then necessary to fertilize and irrigate regularly. In this way, you can also have a beautiful persimmon tree on the balcony, as long as the slab can bear the weight of a large vase.
Cultivation in detail
Pollination. Even if they are not strictly necessary, pollinators are useful for obtaining fertilized fruits instead of parthenocarpic, and therefore less subject to dropping and not astringent when harvested.
Irrigation. Persimmon is a hardy species and tolerates periods of drought well. However, it is good to provide emergency irrigation in particularly dry summers in order not to penalize the size of the fruit.
Mulch. After planting the persimmon tree, it is useful to prepare mulching, a technique used to contain the growth of weeds that tend to steal water and nutrients from the fruiting tree. We can spread black sheets along the entire row or simply surround the base of each plant with a thick layer of straw or cut grass, previously kept to wither to avoid fermentation.
Pruning the persimmon
Forms of farming.The jar it is the most suitable training method for this species as it favors a development in width by reducing that in height. From the central trunk the 3 or 4 main branches open at about 70-80 cm from the ground, from which the secondary branches and the branches on which the fruiting branches are formed develop.
Pruning technique. When setting up persimmon pruning, some important aspects must be kept in mind. The first is that the persimmon bears fruit on the branches of the year, or the buds that are generated in spring and that emit flower buds. The second aspect is the abundant drop of fruit, greatly favored by parthenocarpy. This feature requires you to prune sparingly leaving a generous charge of flower buds. At the same time it is necessary though thin out too dense branches because the fruit drop increases with the lack of light in the foliage, a drawback that also favors the presence of scale insects.
Therefore, even if it is not easy to predict the actual production of the persimmon plant, towards the end of winter the branches must be thinned out so that the remaining ones are adequately distant. Shortenings are indicated when it is necessary to stimulate vegetative activity in certain points, and in this case the terminal portion of the branch, rich in fertile buds, is removed. The shoots that grow from this point will evolve into branches later and bear fruit in the following season. The persimmon rarely emits suckers at the base, while you can find suckers, that is, the vertical branches that start from above and which need to be removed.
Diseases of the plant
Persimmon is occasionally affected by diseases such as teabacterial mood or the gray mold, which can be hindered in their propagation by treatments with copper green, performed with the necessary precautions and by first reading the label on the packaging. Sometimes he is attacked bypowdery mildew, which stops by spraying sodium bicarbonate dissolved in water.
Sesia. Persimmon can be affected by an insect called Sesia, a polyphagous moth (butterfly) that also attacks other species. The damage is caused by the larvae that dig tunnels in the bark and enter the wood and compromise the internal vessels. Indications of the presence of Sesia are widespread yellowing and stunted development of the plant, in worst cases withering. After the fall of the leaves in autumn it is useful to brush the trunk and branches of the persimmon plant with metal tools to eliminate all the wintering forms that have sought shelter in the crevices of the bark, with particular attention to the grafting point and the point of insertion of the branches . We can also do treatments with a bioinsecticide based on the nematode Steinernema feltiae, both on the wintering forms and during the season on the flickering individuals.
Fruit fly. Persimmon can be damaged by the fruit fly (Ceratitis capitata). A useful preventive strategy to defend the tree from this insect is to always complete the harvest without leaving fruit on the plant beyond ripening, because this would increase the insect attack sites. Against the fruit fly you can do some ecological treatments such as the one with the kaolin, very fine clayey mineral to be dissolved in water and sprayed on the foliage (at doses of 2-3 kg / hectolitre). This has a deterrent effect on the insect because it creates a white patina on the leaves that prevents it from recognizing the plant while not hindering chlorophyll photosynthesis. At the beginning of the season it is useful to install Tap Trap type food traps for mass trapping, and finally treatments with the fungus can be done Beauveria bassiana or with the organic insecticide Spinosad.
Cochineal. The persimmon can also be affected by scale insects, which move away by spraying on the plants macerated fern or dealing with mineral oils.
Nematodes. To prevent nematodes, tiny soil organisms that can damage persimmon roots, one tip is to sow lots of marigold flowers under the foliage and around the plant. Maybe this is not easy to do in an orchard, but with a single plant in the garden it can be done.
Collection of persimmons
Persimmons must be harvested before full ripeness, when they are still hard. Leaving persimmons on the plant until fully ripe carries the risk of cracking and blackening on their delicate skin.
Usually the persimmon harvesting period is late autumn, around October-November, when most of the fruit trees have already produced for some time. This means that in a mixed organic orchard, khaki plants are a resource that allows the production season to be extended to the maximum, especially in areas where citrus fruits cannot be grown as winter fruits.
A curiosity: in many persimmon fruits there are seeds, by opening them you can recognize cutlery shapes, in popular tradition they are used to predict what winter will be like.
Since the persimmon plant can grow a lot, a ladder must almost always be used for harvesting, but with the utmost care. Before the operation it is advisable to obtain low crates, which are the ideal containers because they allow you to arrange all the persimmons collected in single layers. About 30-40 kg of fruit can be harvested from an adult plant.
Variety of persimmon
There are not many varieties of kaki grown in Italy. The best known is the khaki Type, the well-known orange khaki which after harvest becomes red, sweet and deliquescent. The Khaki Vanilla, also called "khaki apple"Is the one that can produce parthenocarpic fruits ready for consumption at the time of harvest since they are not astringent. Particularly resistant to diseases and widespread in the south is the variety of khaki Chocolate, which produces medium-small, sweet and aromatic fruits.