Differences Between Kyoho and Summer Black Grapes and Their Cultivation and Management Methods

As people's living standards improve, many kinds of fruit have appeared on the market to meet demand. Kyoho grapes and Summer Black grapes are exactly the grape varieties we often cannot tell apart. So what are the differences between Kyoho grapes and Summer Black grapes? How should they be cultivated and managed? Let's take a look below.

Summer Black grapes originated in Japan and are a descendant of Kyoho. They are sweet and delicious, slightly tart, with skin that clings tightly to the flesh, so they can be eaten without peeling. They are one of the most delicious grape varieties on the Chinese market.

Kyoho grapes belong to the mid-season, tetraploid category and are a European-American hybrid, originally from Japan. They were introduced to China in 1959 and widely promoted across the country, becoming a main variety deeply welcomed by fruit growers.

I. What are the differences between Summer Black grapes and Kyoho grapes?

1. Kyoho grapes are tetraploid and normally have seeds; Summer Black grapes are triploid and normally cannot develop seeds. So the biggest difference between Kyoho grapes and Summer Black grapes is that Kyoho grapes have seeds, while Summer Black grapes do not. If the Summer Black grapes you eat have seeds, you may have eaten “fake Summer Black grapes.”

2. The skin of Kyoho grapes can be peeled off very easily and stays intact, while the skin of Summer Black grapes is not so easy to peel.

3. Summer Black grapes are characterized by early ripening; compared with other grapes that ripen in August, including Kyoho grapes, they ripen earlier.

4. Summer Black grapes ripen earlier than other grapes, so their price is generally higher than that of other grapes.

II. Which is more expensive, Summer Black grapes or Kyoho grapes?

Summer Black grapes are characterized by early ripening, being seedless, high in sugar and low in acid, with a rich aroma, fine and crisp flesh, and medium firmness, and they ripen earlier than other grapes that mature in August (including Kyoho grapes). So relatively speaking, Summer Black grapes are more expensive.

III. Cultivation and Management Techniques for Summer Black Grapes

Summer Black has strong growth vigor and very good flower bud differentiation; even plump thin branches can produce flower clusters. The leaves stand upright, the leaf color is dark green, and the photosynthetic efficiency is high, making cultivation and management easy, with even better results under forcing cultivation. It can be propagated by cuttings or grafting.

For young tree management, the trellis style uses a “high, wide, drooping T-shaped trellis.” In addition, Summer Black is also suitable for trellis cultivation.

Dig trenches and apply fertilizer. Before planting, dig trenches and apply fertilizer, plant at a spacing of 1m between plants, and after planting water thoroughly to settle the roots and cover with plastic film.

Bud rubbing and shoot positioning: after sprouting, remove double buds, multiple-head buds, and overly weak buds; after new shoots form, train them along the wires on both sides and position the shoots at 15-20cm spacing.

Cluster thinning to set yield: from bud break to the early flowering stage, remove overly large clusters and weak small clusters.

Flower and fruit thinning: Summer Black has a very high fruit-setting rate. One week before flowering, remove the secondary cluster and several branch axes below the secondary cluster, lightly pinch the tip of the cluster or even do not pinch it at all, in order to maintain a conical cluster. After flower drop and fruit drop have stabilized, thin the fruit.

Girdling: when applying the swelling agent for the first time, girdle the main trunk branch, with a width of 2-3mm, deep to the xylem, then bind the wound well with tape, which can promote berry enlargement. Girdling when the berries just begin to color can advance ripening.

Topdressing with swelling fertilizer: generally, after flower fall, promptly apply fully decomposed chicken manure or cake fertilizer, at 200kg per mu, combined with 30kg of ternary compound fertilizer and 10kg of potassium sulfate, applied in two split applications.

Topdressing with coloring fertilizer: when the berries turn color, apply 10-15kg of potassium sulfate per mu. Combined with pesticide spraying, add foliar fertilizer of 0.3% monopotassium phosphate or 0.6% Baolifeng No. 2.

Control excessive growth of new shoots: after bagging the fruit, especially during the coloring period, strictly control the growth of new shoots; this is the key to Summer Black management. Otherwise, coloring will be slow and ripening delayed. The growth of new shoots can be suppressed by pinching or spraying chlormequat on the leaves, but the most important thing is to control the amount of nitrogen fertilizer and increase the proportion of phosphorus and potassium fertilizers. After several years of planting, thinning can be carried out to expand the canopy and maintain growth balance.

Autumn base fertilizer: after fruit harvest, at the end of August and beginning of September, combine with deep plowing and apply 4000-5000kg of decomposed organic fertilizer (such as pig manure) per mu, 50kg of superphosphate, and dig trenches to form high ridges.

IV. Cultivation and Management Techniques for Kyoho Grapes

1. Timely bud rubbing and reasonable pruning

In the complete guide to Kyoho grape cultivation techniques, after grapes sprout in spring, promptly remove double buds and small buds and retain strong buds. Before flowering, pinch the main shoots in a timely manner in 2-3 rounds, remove secondary shoots, so that more nutrients are transported to the flower organs, and at the same time appropriately thin some flower clusters, and 3-5 days before flowering pinch off 1/4-1/5 of the end of the flower cluster, so that nutrients can be concentrated to supply the remaining berries. In winter, adopt medium-long cane pruning, leaving about 10-15 new shoots per square meter of trellis surface, staggered above and below, ensuring each cluster of grapes grows to 15-25 leaves, and controlling yield within 2500 kg per mu. In this way, the clusters can be compact, the berries uniform, and ripening consistent, improving the flavor and color of the berries.

2. Strengthen fertilizer and water management to prevent premature decline of the tree body

In the complete guide to Kyoho grape cultivation techniques, Kyoho grapes have strong growth vigor and relatively high requirements for fertilizer and water conditions. But irrigation should be moderate; especially 15-20 days before picking, watering must be stopped. The amount of nitrogen fertilizer applied should be controlled, and phosphorus and potassium fertilizers should be increased. For vineyards that have begun to bear heavily, attention should be paid to increasing fertilizer application to keep the tree body robust and extend the years of full fruit production.

Watering: after the grapes are uncovered in spring, water once to promote budding. Before flowering, if the soil is not overly dry, try not to water. After flower fall, the fruit enters a period of rapid swelling, which is the period of greatest water demand, and it can be watered once every 10 days. Once the berries begin to color, stop watering to increase the soluble solids content of the fruit. Before burying the vines in soil for winter, irrigate heavily once to help the grapes overwinter safely.

3. Measures to increase the fruit-setting rate of Kyoho grapes

Flower and fruit drop in Kyoho grapes is a common problem in production. Its main causes are poor development of flower organs, inability to pollinate and fertilize normally, adverse climatic conditions during the flowering period, and nutritional imbalance within the tree. In production, the following technical measures should be taken to increase the fruit-setting rate of Kyoho grapes.