Can you recommend some narrow or fastigiate trees for the space between our house and the house next door? The space is about 14 feet wide. Will Cornus kousa ‘National’ work?
From what the experts say, Cornus kousa grows 20-30 feet high and wide in cultivation. They can grow to twice that size in the wild.
I found this and other information that might help you in the sources below:
1. Trees and Shrubs for Pacific Northwest Gardens, by J. Grant, 1990, p. 71
2. Trees & Shrubs Hardy in the British Isles, by W.J. Bean, 1976, p. 703
3. Manual of Woody Landscape Plants, by M. Dirr, 1998, p. 260
4. North American Landscape Trees, by A. Lee Jacobson, 1996, pp. xiii, 144
The Seattle City Arborist’s Office recommends the following narrow trees:
1. Magnolia grandiflora ‘Little Gem’ – 15 ft. high, 10 ft. wide. White flowers, evergreen.
2. Malus ‘Adirondack’ – 18 ft. high, 10 ft. wide. White flowers, red fruit, excellent scab resistance.
3. Malus ‘Red Barron’ – 18 ft. high, 8 ft. wide. Red flowers, red fruit, yellow fall color.
4. Malus ‘Golden Raindrops’ – 18 ft. high, 13 ft. wide. White flowers, yellow fall color, abundant yellow fruit.
5. Prunus serrulata ‘Amanogawa’ – 20 ft. tall, 6 ft. wide. Pale pink double flowers, bronze fall color.
Here are additional sources: