Q. What trees would be appropriate for a terrace in NYC?
Growing trees on a terrace is much more difficult than growing them in a garden. The main problems to be contended with are intense sun and high winds. Practical considerations such as the size of the root ball associated with a mature tree, the amount of soil that a terrace can hold and the availability of water are also important.
For these reasons it is preferable to select dwarf varieties of trees unless adequate space is available and weight considerations are not important. Also, pay particular attention to the hardiness of the suggested trees. Trees that may be suitable for a street level garden may not be hardy in an exposed location.
Here is a list of some possible trees:
Eastern white pine. Pinus strobus. Hardy to USDA Zones 2 - 3. 'Coney Island' is a dwarf varietyL
Mugo pine. P. mugo. To Zone 2. 'Paul's Dwarf' is a miniature variety.
Limber pine. P. flexilis. To Zone 4. 'Vanderwolf's Pyramid' and 'Bergman's Dwarf' are dwarf varieties.
Hinoki cypress. Chamaecyparis obtusa. To Zone 5. 'Nana Lutea' is a dwarf variety.
Eastern hemlock. Tsuga canadensis. To Zone 3. 'Jervis' is a dwarf variety.
Eastern red cedar. Juniperus squamata. To Zone 4. 'Blue Mountain' and 'Blue Star' are dwarf varieties.
Other trees and shrubs
River birch. Betula nigra. To Zone 4. 'Little King' is a dwarf variety.
American dogwood. Cornus florida. To Zone 5. Suitable for a large terrace. Dwarf varieties are also available, e.g. 'Little Princess' and ' Suwanee Squat'.
Kousa dogwood. C. kousa. To Zone 5. Suitable for a large terrace. Dwarf variates are also available, e.g. 'Little Poncho'.
Japanese maple. Acer palmatum. To Zone 5. Suitable for large terrace. Dwarf varieties are also available, e.g. 'Red Dragon'.
Serviceberry. Amelanchier spp. To Zone 3. Suitable for large terrace. Dwarf varieties are also available, e.g. 'Regent'.
Harry Lauder's Walking Stick. Corylus avellana 'Contorta'. To Zone 4.
Smoke Bush Cotinus coggygria. To Zone 5. Suitable for a large terrace. For smaller terraces it can be pruned back drastically each spring (although it will not then flower)..
Mountain laurel. Kalmia latifolia 'Elf". Hardy to Zone 5.
Climbing hydrangea. Hydrangea anomala subsp. petiolaris. To Zone 4.
Courtesy of NYBG Plant Information Service