Question
My condo complex needs to plant a row of tall trees to screen our courtyard.  The roots of the current poplar trees have grown down through the concrete well and are causing leaks.  We want something as tall as possible but with non-invasive roots.  I've looked at Italian Cypress (too long of a tap root), timber bamboo,(too invasive) & podocarpus nagi (also invasive according to allexperts.com.  Can you give suggestions??

Answer
Hello Bev

Because most trees (except conifers) are not clothed with leaf down to the ground, I would like to suggest a compromise - shrubs.  Most may not grow way high, but should grow tall enough to provide privacy.

Berberis darwinii - 6ft x 6ft (could get higher).  Has dark green, prickly leafs and orange flowers in the spring.  A good plant to deter intruders!

Cotoneaster 'Cornubia' - 10ft x 10 ft. small, dark green leafs, white flowers in spring and berries in the fall.

Olearia macradonta (New Zealand daisy bush) - up to 15ft high and wide!  Darkish green 'toothed' leafs and white daisy-like flowers in spring.

Viburnum tinus - 4ft x 6ft. white flowers in late winter/early spring.

Escallonia rubra var. macranther - 6ft x 6ft. Shiny green leaves which are aromatic when crushed (some smell very strongly of oranges), pink or red flowers from late spring to fall

Choisya ternata (Mexican Orange Blossom) - 5ft x 8ft.  Palmate (finger-like) leaves which are aromatic when crushed and white scented flowers first in late spring and again in late summer.

All the above plants are evergreen, ensuring privacy all year round and can be trimmed if you want a neat hedge, or left to their own devises for a more informal feel.  Also you can, of course, plant as a single variety hedge or mix them up as you please!

If you want to check out non-invasive bamboo (of which there seems to be many), I have found a web site you may find helpful - www.bamboohq.com.

I hope I have given you some ideas here that you can work with.

Good luck,

Gill