photos needed - rockery and limestone mountains

[mark smyth]

No problem. I read that lichens grow 1mm a year. Mine after 5 years must be on steroids. The stone is liscannor

[Lesley Cox]

Is it correct that lichens grow best in areas where the air is very pure, i.e. no pollutants? If so we must be very pure ( ) because our tile roof is covered with them. Roger wants to clean it but I'm not in favour as A, it looks nice and B, I think the lichens filter out dust and other rubbish when the rain falls, and the occasional dead thing which would otherwise go into our water tank. I know that adds body to the drinking water but.....

[mark smyth]

They are nice looking. Travellers, putting on English accents, come round here all the time asking to jet wash drives and rooves

[Paul T]

Lesley,

That is the usual story.... the one problem I have with that is that one of the major roads (to the main shopping centre in the town centre) in my part of Canberra has trees down the centre of it which are covered in lichen.  There is no way that with that many cars going by every day on each side of the median strip (even if it is quite wide) it could be in any way classified as "pure air" of "good quality" and such.  It makes me doubt somewhat the old statements about lichen indicating good air.

[Paul T]

Mark,

Your little rockeries are inspiring.  I'm tempted to try to build something small like that (although in the garden, not in a trough) except I have no idea where I'd get that irregular flat stone.  I guess I could go for the paving stone stuff, but I would be concerned it would look too regular.  Yours look brilliant!!

[mark smyth]

Good to read people like the troughs. A few things have died and need replaced. There are bulbs in them also - Crocus, small Galanthus, Ranunculus ficaria and Colchicums.

[Lesley Cox]

Paul a good crevice garden CAN be made with paving stones and doesn't look too regular if the spaces between the slabs are varied somewhat. A few centimetres for one space then a few more or less for the next space etc. and once the plants are in and growing, the rock is partially covered anyway.

[Lesley Cox]

Regarding the lichens, it may be more a question of what surface the spores settle on and the general dampness in the air over time. A plastic netting fence near me (windbreak cloth) is covered in lichens yet rock in the same garden has none at all and that particular rock is the local bluestone which is harsh and unattractive in the garden though it made, 100+ years ago, a great building material. But it NEVER "weathers."

[Kees Green]

Not sure its limestone but here isn a pic from our Takitimu Range in Soutland looking toward Fiordland