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Planting Methods and Key Technical Points for the Duabanga grandiflora

Growing Techniques By Emily Carter 0 views
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Duabanga grandiflora (scientific name: Duabanga grandiflora (Roxb. ex DC.) Walp), family Sonneratiaceae. Sonneratiaceae. A large tree, up to 40 m tall, with a diameter at breast height of 1.5 m. Slightly buttressed. Bark grayish white, not fissured. Trunk round and straight. Branches four-angled, drooping. Leaves opposite, entire, long elliptic, 10-30 cm long, up to 10 cm wide, apex acute, base shallowly cordate; pinnate veins, lateral veins numerous, nearly parallel; petiole short. Large corymb terminal;  sepals 5; petals 5, obovate, white, undulate;  stamens numerous; ovary semi-inferior, 4-8 locular, ovules numerous. Capsule spherical, slightly four-angled, dehiscing by 4-8 valves, persistent calyx thickly leathery. Seeds small, with stellate projections at both ends. Flowering period March-April, fruit ripening period May-July. Produced in mountainous areas of southwestern Guangxi, China at an altitude of 200-500 m, and in tropical rain forests in valleys or by streams below 1,500 m in southern Yunnan. Also distributed in Vietnam, Myanmar, Thailand, India and Malaysia. Propagated by seed, natural regeneration is good under open forest or at forest edges. Fast-growing. Because its grain is extremely similar to that of black walnut, it is also called African black walnut.


Duabanga grandiflora is commonly propagated by cuttings and sowing

 Cuttage propagation of Duabanga grandiflora is generally carried out from April to September. Cut 1-year-old top shoots of Duabanga grandiflora, 8-10 cm long, remove the lower leaves, insert them in a sand bed, and keep the sand bed moist, at a room temperature of about 25°C. The cuttings of Duabanga grandiflora will grow new roots 30-40 days after insertion.

  Sowing propagation of Duabanga grandiflora is carried out from April to May, generally sown indoors in pots; the suitable germination temperature for Duabanga grandiflora is between 20-25°C; after sowing, keep the pot soil moist, and the seeds of Duabanga grandiflora will germinate in 15-20 days. When the Duabanga grandiflora seedlings are 5-8 cm tall, they can be transplanted into pots.

  Containers: potted Duabanga grandiflora generally uses a 15-20 cm pot, and the bottom of the pot should be lined with more broken tiles or broken bricks to facilitate drainage.

  Light: in summer, Duabanga grandiflora needs to be shaded with a 70% shade net to avoid scorching the leaves by the hot sun.

  Watering: Duabanga grandiflora likes an environment with high air humidity and sufficient soil moisture. When growing Duabanga grandiflora, keep the soil moist; do not wait until the soil is completely dry before watering. Water in time, and when the weather is dry, also spray water around Duabanga grandiflora to increase air humidity.

  Fertilizing: during the growing period of Duabanga grandiflora, fertilize once every half month or use "Huiyou" 20-8-20 all-season high potassium nitrate fertilizer.

  Pruning: when Duabanga grandiflora sprouts leggy branches, pay attention to shaping and pruning. Young plants of Duabanga grandiflora need thinning and light pruning, mainly for shaping. When old plants of Duabanga grandiflora become too large, heavy pruning is needed for adjustment.

  Repotting: young plants of Duabanga grandiflora are repotted every spring, and adult Duabanga grandiflora is repotted once every 2 years.

Main value:


Wood yellowish brown, somewhat coarse in texture, straight-grained, somewhat light and soft, easy to dry, not prone to warping or cracking, suitable for construction, furniture, packing boxes, boards and other timber uses.
The heartwood and sapwood of Duabanga grandiflora differ greatly. The sapwood has low strength, coarse texture and poor quality, but it can be used for matchsticks; the heartwood is good in quality, hard, and can be used for doors and windows, beams, furniture, etc., with good decay resistance and not easy to deform or warp and crack.



The wood is diffuse-porous. The distinction between heartwood and sapwood is indistinct to slightly distinct; heartwood slightly grayish brown to purplish brown; sapwood grayish brown to light yellowish brown with a slight red tinge, often mixed with golden yellow or blue patches, 4-5 cm wide. Growth rings indistinct to slightly distinct. Width uneven (3-10 mm). Pores visible to obvious under the naked eye; number very few to few; medium to slightly large; size fairly uniform, distribution slightly even; solitary and in short radial multiples (2-3); scattered, tyloses not seen, occasionally white deposits. Vessel grooves very obvious on longitudinal sections. Axial parenchyma scanty; visible under a magnifying glass, paratracheal. Rays non-storied; medium to slightly dense; very fine to slightly fine; visible only under a magnifying glass; very fine ray flecks on radial sections, indistinct. Ripple marks and intercellular canals absent.
The wood has weak luster; the heartwood has a slight sour odor, no special taste; grain straight; texture medium to slightly coarse, uniform; wood light and soft (air-dry density 0.44-0.51 g/cm3). Suitable for packing boxes and cases, pulp, canoes, low-grade plywood and furniture, insulating materials, light-frame house construction, etc. The wood contains a large amount of yellow pigment.



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