Raised flower border

Other groundworks tasks, such as roads and footpaths, terracing, fencing, foundations, walls and brickwork, tools and plant.
Post Reply
Dave Meredith
Posts: 2
Joined: Thu Sep 12, 2019 4:31 pm
Location: Tewkesbury

Post: # 117782Post Dave Meredith

My neighbour has quite a large tree close to the fence. It overhanges into my garden and unfortunately very little grows under its shade. I've trimmed a few branches back so its not too shaded but the tree takes most of the water and nutrients to the point where the lawn hardly grows at all.
I would like to build a raised flower border under this overhanging tree. I don't want a straight border so I'm thinking of using upright railway sleepers and backfilling with soil. I was thinking of putting some kind of moisture barrier in before backfilling with soil because I dont want the tree roots growing up into my raised bed and I want the rainfall to be retained in the bed -not absorbed by the tree roots.
Is this a workable solution? Are there any issues I should be aware of and do you all think this should work?
Many thanks
Dave

Tony McC
Site Admin
Posts: 8346
Joined: Mon Jul 05, 2004 7:27 pm
Location: Warrington, People's Republic of South Lancashire
Contact:

Post: # 117783Post Tony McC

You need to strike a balance between creating a pond or reservoir for moisture, and building a feeding station for the damned tree, so the aim would be to fashion a pit with good-ish moisture retention, plenty of nutrition, but adequate drainage.

The basic idea to use upright sleepers is fine, but how much upstand? A good 'rule-of-thumb' would be to have at least one-third (minimum 2200mm) in the ground fully supported, prefeably with concrete, in the manner of a fence post. The 'inside' can then be lined before backfilling with a good, healthy growing medium.

If you have a well-drained plot, the lining can be root- and watertight(ish) with perforated pipes laid at the base and leading out to a soakaway or similar elsewhere in the garden, but for most applications, simply lining with a good quality root barrier membrane or composite, to inhibit encroachment from the tree roots, would be adequate and by far the simpler construction.

You may have to provide irrigation or regular watering if the tree is going to parch the plot, but that applies to most tree-lined gardens anyway, so no great additional burden.

It'll be interesting to hear how you get on.....
Site Agent - Pavingexpert

Dave Meredith
Posts: 2
Joined: Thu Sep 12, 2019 4:31 pm
Location: Tewkesbury

Post: # 117787Post Dave Meredith

Many thanks for your response Tony. It really
helps to have a second opinion especially from
someone with expoerience.
This border will not be huge - probabaly a half-circle with
a radius of 1.5 metres. I'm thinking of a height of about
half a metre or less.
I'm inclined to go with your membrane suggestion. My garden isn't that big and putting a soak-away in is going to cause more disruption than it's worth.
Once again - thank you!

Post Reply