Description Family Sapindaceae. Originating from Japan. An upright, densely branched shrub or small tree with red-black young growth. Lush foliage is one of the truest reds, turning purple and then crimson in winter. Easy to grow, it is ideal for planting in pots or growing in the ground. The Upright Red Japanese Maple in Your Garden This slender variety’s dense, fiery column of soft-textured spring and autumn foliage sets gardens alight. Its more mellow, summer-bronzy-purple tones are intense, dark and dramatic. Its striking upright form is perfect for small gardens and patios, where its abundant leaves are seen close-up. Twombly’s Red Sentinel’ is a compact upright variety. It stays narrow for many years, growing slowly to around 3–4m tall and 2.5m wide over 10-20 years. Planted in sunny spots in Norfolk’s woodland gardens, it makes a striking specimen. On Suffolk’s sheltered patios, it makes a tactile potted focal point while taking up little space. The leaves are deeply lobed and among the truest reds, holding their coral-crimson tones into early summer. New growth appears bright crimson, maturing to a darker burgundy-red with green hues in late summer. In autumn, the leaves have a late flourish of brilliant red. After falling, they leave their dramatically coloured, dark red-black branches for a winter effect. Did you know? ‘Twombly’s Red Sentinel’ gets its unusual name from the nurseryman Ken Twombly, who discovered it as a sport of the popular Acer ‘Bloodgood’ Growing Tips for Your Acer Red Sentinel Soil and sun: Use ericaceous compost for potting. Plant out in any non-alkaline humus-rich soil. Happy in part shade, it also thrives in full sun, where its colours are most intense, as long as the soil is moist. Planting: at any time of year. Plunge the pot or stand in water for 15 minutes to drench before planting. Do not add soil improvers. Watering: Keep soil moist but never waterlogged. Water regularly during dry spells in the first few years. Pruning: Minimal pruning required. Trim in mid-winter to maintain the columnar form of older plants if desired. ‘Twombly’s Red Sentinel’ was selected in the USA for its strong upright habit and reliable red colour. We rarely recommend deciduous plants for contemporary and formal plantings, but its architectural form makes it an exception. This exceptional upright red Japanese maple can hold its own amongst evergreen structural plants and provide dramatic contrast. Planting Suggestions for Acer palmatum ‘Twombly’s Red Sentinel’ Plant a towering array of upright forms to enclose intimate spaces, dramatise paths and gates, creating a vertical vista of exceptional foliage. Plant groups of Pinus ‘Stowe Pillar’ and the dwarf columnar Cedars ‘La Fontaine’ and ‘Karl Fuchs’, interspersed with Red Sentinels. Their silvery foliage and the addition of Caolcedrus decurrens‘ dark, rich green leaves will enhance the maple’s fiery tones. Dramatise your Upright red Japanese maple by planting soft, undulating species around it. Add Nandina ‘Seiku’, Pittosporum ‘Bannow Bay’ and ‘Tom Thumb’ to complement the sentinel’s red and purple colours. Turn up the heat by adding the warm golds and acid yellows of Euphorbia ‘Prampton Phatty’, epithymoides, and ‘Bonfire‘. Alternatively, add calmer, soft green Pittosporums ‘Beach ball’ and ‘County Park’.
