Hi.

Many of you very kindly assisted us some time back with suggestions of
shallow-rooted evergreens for the 12" of soil that covers our
septic-tank drainfield. Some people suggested heathers. Well, the
whole area has now been planted with heathers, some herbs, and lots of
alpines and with all the rain we've been having it's coming along fine.

But a visitor this last weekend has suggested that to give the area more
vertical interest, i.e. some plants of height (every species we've
planted being rather low or flattish) we put in a few tree-heathers here
and there.

So I have googled tree-heathers and it seems this may be an excellent
idea. However, I see that some of them, delightfully, can reach 3
metres in height! So, bearing in mind, that every plant on this
drainfield MUST be SHALLOW-ROOTED, can anyone with direct hands-on
experience of tree heathers assure us that tree heathers, like ordinary
heathers, ARE also shallow-rooted?

We can't afford to have roots that seek to penetrate deeper than 12
inches because they'll penetrate the plastic sheath over the rock bed
and block up the drainage system.

Some of the tree heathers I've been able to find via Google a

Australis.
Tree like shrub reaching 2mt evergreen with pinkish white flowers April
to May, requires a sheltered position. Size

Lusitanica.
The largest of Tree Heather`s 3mt upright and bushy, feathery bright
green foliage, white tubular flowers pink in bud December to February.
Size

Lusitanica George Hunt.
Tree Heather of up to 3mt, evergreen golden foliage, requiring a
sheltered position.

Arborea Alpina.
Tree Heather with young bright vivid green foliage, reaching up to
1.2mt, long stiff spikes of fragrant white flowers January to March.

Arborea Estrella Gold.
Tree Heather with young bright yellow foliage, reaching 1mt in Size,
white fragrant flowers February to March. Size

Thanks,
Eddy.