Densely filled with spiny branches and three-lobed leaves, hardy orange also bears lemon-flavored, small golden fruits that persist into winter. A large shrub to small deciduous tree that is rounded, it is native to northern China and Korea. The fruits are loaded with seeds and will self-sow in landscapes, and with a viciously spined canopy, makes it difficult and unpleasant to remove. It is considered an invasive woodland intruder in some parts of the eastern United States.
The compound leaves are made up of three oval leaflets, first emerging glossy green and maturing to a medium matte green. The leaves occur all along the young green branches that are lined with sharp spines. In late spring or early summer, cup-shaped white blossoms can be found on branch ends. They are pleasantly fragrant and often recur again in early autumn. The green golf ball-sized fruits ripen to yellow-gold by autumn and persist into the winter. Fall foliage is yellow, and once the foliage drops, the lingering fruits look pretty against the zig-zagging olive-green branches across the winter months. Those of 'Flying Dragon' are much more twistingly ornate.
Grow hardy orange in full sun to considerable shade in any fertile well-draining soil. It is very drought tolerant once established, but in the coldest reaches of its hardiness range, it should be protected from drying winter winds. Use it as an impenetrable hedgerow or as a mixed border accent. Position the plant away from walkways or areas where people would not unknowingly walk into the branches. The fruits are edible but very acidic and seedy. They are usually made into marmalade and the zest can flavor culinary dishes. The disease-resistant and hardy roots of this plant are also used as grafted rootstock for traditional citrus tree cultivars. (info source: Learn2Grow.com)
Genus - Poncirus
Species - Citrus Trifoliata
Common name - Winter Hardy Orange
Pre-Treatment - Required
Hardiness zones - 6 - 9
Height - 8'-18' / 2.4m - 5.5m
Spread - 6'-15' / 1.8m - 4.6m
Plant type - Tree
Vegetation type - Deciduous
Exposure - Full Sun, Partial Sun, Partial Shade
Growth rate - Medium
Soil PH - Acidic, Neutral
Soil type - Clay, laom, Sand, well drained
Water requirements - Drought tolerant, average water
Landscape uses - Edible, Hedges, Mixed Border, Screening / Wind Break
Germination rate - 70%
Bloom season - Late Spring, Early Summer
Leaf / Flower color - Green / White
|Germination||1. Soak in warm water for 24 hours.|
2. Cold/moist stratify in moist vermiculite or sterile soil in air tight container/ bag for 4 weeks
3. Sow early spring in a greenhouse.
Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in early summer. Cuttings of half-ripe wood, June/July in a frame.