fine tree roots

by Cosimo Sorrenti
(Batemans Bay NSW 2536.AU)

I have dug a trench 300mm deep around my raiced vegie garden and placed colorbond steel sheeting as barrier to prevent roots from adult gum trees taking all the goodness, (10 metres away at nearest point of garden) to no avail. Everything I plant after preparing the soil grows great for the first 4 weeks, no amount of feed or water seems to help after that, each time I turn a clump of soil and shake it I end up with handfull of fine tree roots. What else can I do?

Doug says that you need to make sure there are no holes in the barrier you're building. Sheets of steel will have spaces between them so you need to seal those off. Landscapers will often use heavy duty landscape fabric as a root barrier.

And yes, in practical terms trees will invade darn near anything you do - up to and including a concrete barrier it would seem (over time anyway)

Four weeks however tells me your barrier really isn't doing anything at all.

Or - your soil organic content is so poor or your water levels are so poor that the plants simply won't grow (assuming annuals). Perennials will grow top-growth quickly for the first few weeks but then start putting root growth on. So not only do you have root issues, you might have a growing issue or a plant-understanding issue. Or you're trying to force plants to grow in wrong light levels. Four weeks with minor root competition indicates a cultural problem of some kind.

That's also assuming the roots in the garden area where well chopped up and the major roots removed (many tree roots will send up shoots and keep developing new roots once they've been separated from the main tree - I don't know how those gum trees work (they don't grow in USDA zone 4) ;-)

So - that's all I can tell you for now. Make sure the roots are removed, seal the edges of the barriers so nothing can get through and watch your cultural stuff.

Good luck