vegetables. Anyone know what I can do? I've just removed a 12ft area of paving slabs from my back garden and wanted to use the area to grown vegetables but the soil underneath the slabs is full of root runners that go in all directions, and they are tough things! When I start pulling one up it runs the whole length of the 12ft area like an underground cable. I have been chopping these roots and cutting them up, but need to remove them completely.

Is there any way I can cultivate this area of my garden and is there something I can use to break up these root runners, please?. As it stands, I could maybe grow surface vegetables like cabbage, cauliflowers, brussels etc, but I wouldn't be able to grow root vegetables like carrots, beetroot, parsnips, as they would be damaged by these roots. The soil is lovely and plants grow really well in it.

Our garden is surrounded by bushes and a couple of trees, but the runners don't seem to be tree roots and the bushes are a distance away from the area. Hope someone can help?

Rototill, rototill, then rototill again. You probably have tree roots to deal with. You will probably need a pro to help you find out what the roots belong to. You may end up killing a tree, which turns into a HUGE expense. It's worth a phone call.

A mature tree, depending on the type, can produce root runners that go 20 to 30 feet. Removing them shouldn't hurt a tree too much. But, be aware that the runners are coming from something and removing them may damage the source plant.

Regarding removing the runners, there's not much you can do except dig them out. The soil in a vegetable garden should be free of obstructions (like root runners) to a depth of at least the head of a standard spade-type shovel. So, using such a shovel, start at one corner of the area you are preparing and dig out a shovel full of dirt.

Keep digging out shovels full of dirt, turning the next clump into the hole you made with the previous one. As you encounter a root runner, pull it up as much as you can. Then start digging where you think its running to. The goal is to pull it all the way out. To cut it, you can use the shovel itself (hack away at the root) or use a pickaxe to hack the root runner off at the edge of the garden.

Continue until the entire bed is tilled and free of roots. Grade the plot with a hard metal rake and the shovel. And, go ahead and toss out any rocks you find in there, too.

I live in the southeast and have managed commercial landscape operations from texas to fla. as well as made I don't know how many personal veggie and flower plots. very seldom have i not found your situation, when preping a new spot.
unless u have bushes next to ur plot, very unlikely to hurt them and it is extremely unlikely to hurt a tree and it is very likely it is either tree roots or tree like shrubs like crepe myrtle. small roots like you are experiencing can run forever, it seems, certainly well past the water line of trees.
the best method is to just chop em up. you don't want to just process actualy planting spots, u need to always prepare the entire area, so if it is with a pair of snips or an axe or machete or a roto tiller, just chop em up, remove the pieces and prepare as you would anywhere else.
I plant in deep, double dug beds, anyway, incorporating organic matter such as compost, rotted manure, peat ... and then bed it up. very seldom is the encroachment of the roots more than an occasional problem, if bed prep is done well and a foot deep. be careful w/ too much rototilling, it creats a shallow hardpan, a hardened subsurface "floor" only 6 or so inches below the surface, making it hard for your plants roots to penetrate.