Grafting Methods for Weeping Crabapple and Key Points for Post-Grafting Care and Management

Growing Techniques Jan 1, 1970 0 views

Weeping crabapple is an excellent landscaping tree species whose flowers, fruit, branches and tree form are all ornamental. Common weeping crabapple cultivars in China include 'Red Jade', 'Louisa' and 'Royal Beauty'. The fruit of weeping crabapple is also edible or can be made into candied fruit. At the same time, the flowering branches of weeping crabapple can be used medicinally to regulate menstruation and harmonize blood.

1 Grafting Techniques for Weeping Crabapple

Weeping crabapple is mostly propagated by grafting, using rootstocks such as Malus 'Hopa' and other crabapples with a tall, straight trunk, and using superior weeping crabapple cultivars as scions.

1.1 Grafting Time

In March to April, when the sap begins to flow, the bark-grafting method is used for top-grafting and changing the head of weeping crabapple. Note that grafting should be done avoiding rainy days.

1.2 Collection and Treatment of Scions

Select plants of weeping crabapple 'Red Jade', 'Louisa' and 'Royal Beauty' with pure cultivar characteristics and robust growth, cut 1-year-old well-developed branches into segments 12-15 cm long with 2 pairs of plump buds, wrap the top end with plastic film to prevent water evaporation, cut one side of the lower end into a 2-3 cm single bevel, and cut the back end into a 0.5-0.8 cm small bevel, remove the leaves and keep the petioles.

1.3 Selection of Rootstock

Select Malus 'Hopa' with a diameter at breast height of 6.0-8.0 cm and a straight trunk as the rootstock.

1.4 Grafting Method

Select rootstocks with basically consistent diameter at breast height and crown width, cut them off at a trunk height of 2.5 m, and use a grafting knife to cut a 3-4 cm long incision downward from the edge of the cut surface. Using the bark-grafting method, immediately insert the prepared scion into the cortex at the rootstock incision and fix it in place. After grafting, bind tightly with plastic film from bottom to top up to the joint to prevent water loss. Generally, 3-4 scions are grafted onto each main trunk.

2 Post-Grafting Care and Management Techniques for Weeping Crabapple

2.1 Checking Survival Rate and Re-Grafting

Check the grafting survival situation 20-30 days after grafting, and promptly re-graft those that have not survived.

2.2 Removing Suckers

After grafting, observe the sprouting of new buds on the rootstock and scions. When the new shoots of the scions grow to 10-12 cm, remove all sprouts on the rootstock except those of the scions, so as to direct nutrients to the scions. After that, remove one sprout every 5 days until no new sprouts emerge from the rootstock.

2.3 Reinforcement Treatment of New Scion Shoots

As the new scion shoots continue to grow, the leaves gradually increase and enlarge. Therefore, in the later stage, in addition to removing suckers, the new scion shoots should also be fixed in place. Supports can be used around the scions for reinforcement to prevent the joint from loosening due to wind swaying. When the new shoots grow to 50 cm, promptly remove some leaves to avoid the new shoots becoming too heavy due to excessive leaves, which could cause the scions to break or fall off in the wind.

2.4 Fertilizer and Water Management

Seven days after grafting, when the rootstock and scion have basically healed, begin the first thorough watering. About 20 days later, check the survival of the grafted seedlings and water thoroughly once more along with fertilization. From May, apply N, P, K compound fertilizer at 150-225 kg·hm-2, which can be applied 2-3 times throughout the year, with timely watering combined with fertilization. After watering or rainfall, loosen the soil and weed in a timely manner to conserve moisture. After leaf fall, stop fertilizing.

2.5 Shaping and Pruning

Reasonable pruning should be carried out in the year the graft survives. Generally, shaping and pruning are done to form an umbrella shape, and the pruning method can reference that used for Ulmus pumila 'Pendula'. Prune according to the principles of "well-spaced density, keep the superior and remove the inferior, evenly scattered." Generally, after 3-4 years, a tall weeping crabapple can be cultivated.

Care Methods for Wintersweet Bonsai: Making and Caring for Wintersweet Bonsai

All kinds of bonsai appear in different places; everyone has their own preferences. Today our topic is wintersweet bonsai. Wintersweet blooms in winter, a very beautiful flower. Do you want to grow it? When you see it, don't you think it blooms beautifully? This is when it has just bloomed; it has opened after withstanding the test of severe winter. In the cold weather of winter, it can still bloom so brilliantly. Let's take a look at how to grow wintersweet bonsai.

I. Introduction to Wintersweet Bonsai

Wintersweet (Chimonanthus praecox) is a traditional bonsai plant in China. Its tree form is graceful, its roots are quaint, and waxy-yellow flowers bloom on its sparse, slanting branches. It is bright and brilliant, and the fragrance it emits is intoxicating, especially warm and cozy in the cold winter. Wintersweet is a deciduous shrub of the family Calycanthaceae and the genus Chimonanthus. It has many cultivars, with flower colors including pure yellow, golden yellow, pale yellow, ink yellow, yellow-white, pale white, silver white, etc., and flower centers in red, purple, reddish-brown, pure white, etc. More famous traditional cultivars include 'Suxin' wintersweet, 'Tanxiang' wintersweet, 'Huti' wintersweet, 'Qingkou' wintersweet and 'Gouya' wintersweet, as well as fine cultivars such as 'Queen' wintersweet, 'Huti Hongsi' wintersweet, 'Jinpan Yurui' wintersweet, 'Yinzhong' wintersweet, 'Bailian' wintersweet and 'Jianhong' wintersweet.

In Yanling, Henan, the "hometown of wintersweet," traditional wintersweet bonsai forms include single-trunk plum, dragon plum, knot plum, single-hanging-branch plum, double-hanging-branch plum, round-hanging-branch plum, screen-fan plum, pearl inverted curtain, etc. It can be shaped by training young trees with wire, or old, quaint 'Gouya' wintersweet stumps can be used as rootstock to graft superior cultivars such as 'Suxin' wintersweet and 'Qingkou' wintersweet. Its roots swell and take on a knotted appearance, which is called "knot plum."

Because wintersweet branches are relatively brittle and break easily, large-scale bending and shaping are not suitable. Generally, only palm fiber is used to slightly hang, tie and twist the main trunk or large branches, and then the fine branches are lightly pruned. This is generally done from May to August because the branches are soft at this time. Before operating, pay attention to controlling watering to further soften the branches and facilitate shaping.

II. Making Wintersweet Bonsai

Step 1: Sourcing Materials and Cultivation

It is relatively common and quick to achieve results by using wild old root stumps of mountain wintersweet and cultivating them in the ground to make ancient wintersweet stumps. The method is: select old tree stumps that have been cut back and have sprouted over many years, dig them out, taking care to protect the root system, and prune the branches. Choose a location with moderate light, loose soil and good drainage for "nurturing the stock." After it survives, move it into a pot for cultivation. If it is an old 'Gouying' wintersweet stump, 'Suxin' wintersweet can be selected for grafting, and after survival it can be processed and shaped as needed.

Step 2: Potting Process

Wintersweet is suitable for purple clay pottery pots, and glazed pottery pots can also be used. Generally, seedling wintersweet is mostly grown in round pots, square pots, hexagonal pots, etc. Old wintersweet stumps can use medium-deep horse-trough pots or crabapple pots, while cascade styles mostly use tall cylindrical pots. Dark purple or ochre red colors are better, to set off the waxy-yellow flowers and increase their ornamental effect. Wintersweet is not strict about soil, but well-drained sandy loam is best. For potting, decomposed garden soil or leaf mold mixed with 20-30% rice husk ash is commonly used as the growing medium. Wintersweet is mostly transplanted in early spring, preferably around early March before and after the new buds sprout on the flowering stems. Generally, it is best to plant it at a slant to make it easier to create momentum when shaping. Before planting, shaping and pruning can be carried out once. When potting, sufficient base fertilizer can be applied at the bottom of the pot.

Step 3: Shaping and Styling

Although wintersweet and plum blossom do not belong to the same family, their flowering periods are similar, and their flowers and fragrance are also similar. Wintersweet is delicate in color and rich in fragrance, no less than red plum, so the styling principles of plum blossom can be referenced: "Plum is beautiful when curved; when straight it lacks grace; it is beautiful when slanting; when upright it lacks scenery; it is beautiful when sparse; when dense it lacks form," and "Plum is valued for being sparse rather than abundant; valued for being old rather than young; valued for being thin rather than fat; valued for being closed rather than open," etc. Therefore, the main trunk should be slanting and horizontal, the branches and leaves should be sparse and spreading, and the old stump should show strength. In addition to the "screen-fan style," "knot style" and "hanging-branch style" of Yanling, Henan, traditional forms also include "downwind style," "weeping-branch style" and "swimming-dragon style," etc. In current shaping, tree forms are mostly slanting-trunk style and natural style.

III. Care Methods for Wintersweet Bonsai

Placement: Wintersweet bonsai should be placed in a wind-sheltered, sunny location, avoiding cold wind. In summer it needs slight shading. In winter, potted plants should be moved indoors to overwinter when the temperature is below 1°C.

Watering: Wintersweet is relatively drought-tolerant and is known as "the wintersweet that cannot be killed by drought," but it should not be too dry either. Usually the potting soil can be slightly dry. Water according to "water when dry, stop when wet"; if not watering, then do not water, but when watering, water thoroughly. The dog days are the flower bud formation period, and water must not be lacking; water once in the morning and once in the evening. When leaves fall after autumn, the potting soil can be on the drier side, watering once every 5-7 days.

Fertilizing: Wintersweet likes fertilizer. From April to June, in the early stage of flower bud formation, it is suitable to apply cake fertilizer water once every 10 days. From the end of June to before the dog days, apply a dilute fertilizer water combining nitrogen and phosphorus once a week to promote flower bud formation. During the dog days, apply 1-2 times, with thin fertilizer. After autumn, apply once more. When repotting, sufficient base fertilizer such as bone meal and soybean cake can be applied at the bottom of the pot.

Pruning: To make wintersweet have luxuriant branches and abundant flowers year after year, pruning and bud pinching are extremely important. Pruning is generally done from March to June and stopped after August. After flowering each year, the old flowering branches should be immediately cut short, leaving only 15-20 cm at most on each branch. After the new branches grow 2-3 pairs of buds, pinch off the terminal bud. Soon side branches will grow again. After they grow to 10 cm, pinch the buds again. Repeat this several times until the flower buds are basically formed. Also thin out various crossing branches, parallel branches, overlapping branches, opposite branches, water sprouts and overly dense or weak branches that affect the beauty of the tree shape. There is a saying in flower lore that "wintersweet does not lack branches," so wintersweet can be heavily pruned.

Pest and Disease Control: Wintersweet has strong resistance to pests and diseases. Occasionally there are pests such as slug moths, bagworms, aphids and scale insects, which can be controlled by spraying 80% dichlorvos at 1500 times dilution or 90% crystalline trichlorfon at 1000-1500 times dilution.

Finally, let me tell you that using wild old root stumps of mountain wintersweet and cultivating them in the ground to make ancient wintersweet stumps is relatively common and quick to achieve results.

Making Wintersweet Bonsai: Care Methods for Wintersweet Bonsai

I. Introduction to Wintersweet Bonsai

II. Making Wintersweet Bonsai