monterey cypress shallow chalk help

Hi
I want to plant a tree in my ugly front garden, but i have discovered that the topsoil is only about 30cm deep and under that is solid chalk (I live in brighton, uk). I have already bought a 180cm-tall monterey cypress for the site, and so i have been hacking away at the chalk to make the hole deeper. I have now gone 60cm deep (30cm into the chalk) and about 70cm diameter. I plan to fill this hole with shop-bought compost and growmore and stick in the cypress and hope for the best.

Is there any chance at all that the tree will grow, or is it complete madness? I only need it to be around 4-5m high.
If not, how much deeper/wider do i need to dig and/or is there another more suitable evergreen tree? It is a partial sun/shade site (probably 7 hours direct sun in summer)

many thanks

 

Hi.. I used to look after the gardens at Sussex Square in Brighton, (shallow chalk soils) In the Great Strorm of October 1987 we lost over 30 mature Monterey Cypresses, ripped out of the ground, roots and all! Not one was left standing, while some other trees survived (albeit ripped to shreds!)

So.... yes, they will grow quite well, much bigger than 4-5 metres, they are huge trees but not a particularly good choice. especially in a small garden.

Phillyrea latifolia, (the green olive tree) is a better choice will never get too big, can take pruning if neccessary, and stood up to the hurricane on shallw chalk!