Pakistan Gardening Forum

which grass has shallowest root system which will enable it to establish on the roof in a couple of inches of medium

There are shallow root grasses but i doubt any will be able to grow healthy in few inches of media.

Any recommendation (name)?

Hamad

Bentgrass (Agrostis spp.)
Kentucky Blue Grass

Both are said to be less heat tolerant
http://www.ipm.ucdavis.edu/PMG/r785900111.html

Checked up from a clude up owner of a Nursery at Peshawar Mor, Islamabad.As per him,the minimum requirement is 3" for 'filteration/drainage base' ie, pebbles/brick pieces etc & 6" of sweat earth on top for Fine Dhaka, American, Bermuda etc ,but 8" for Korean Grass,which only can be planted in partial shade. Farhan & Umar can guide better.

I have no exact knowledge on the subject, but i wonder won't water seep through the roof? There has to be some specific method for doing this

indeed Farhan drainage is one of the key element in roof top grass and there are couple of methods in place but could be done by self driven technique the purpose is to attain good drainage (anything could be used)

Bentgrass (Agrostis spp.)
Kentucky Blue Grass

are they good for our climate

Checked up from a clude up owner of a Nursery at Peshawar Mor, Islamabad.As per him,the minimum requirement is 3" for 'filteration/drainage base' ie, pebbles/brick pieces etc & 6" of sweat earth on top for Fine Dhaka, American, Bermuda etc ,but 8" for Korean Grass,which only can be planted in partial shade. Farhan & Umar can guide better.

means min is 6" which is a lot of load on the roof don't sounds good

Hamad

Yes load is the main concern.Roofs could be treated with tar and sheets before lying the medium but what to do with extra load?

if couple of inches will do the job, only then its possible otherwise its not achievable

Hamad