How to kill unwanted grass in garden bed?

[samy]

I have inherited a garden patch from the last owners who had let the garden go wild. I removes most of the grass by hand which was growing amongst the plants. Put two layers of hardwood mulch to prevent the grass growing n the garden looked so much better. But after three weeks the grass is growing back.  How do I get rid of this grass?

  

[Jewelleryrescue]

Hi @samy 

You might need to put thick cardboard or black plastic to try sterilse that section of  yard for a whille till the grass is  dead and seed cooked.

[MitchellMc]

Welcome to the Bunnings Workshop community @samy. It's fabulous to have you join us, and many thanks for your question about preventing grass from growing.

@Jewelleryrescue has hit the nail on the head there, as you need to remove the woodchip, lay weed matting, and then place the mulch back over the top. Otherwise, the grass will continue to grow through the mulch.

Please let us know if you have any questions.

Mitchell
 

[RohanMelb]

Hi Mitchell.  I put down weed matt but the grass from the neighbours keeps shooting runners under the matt and up the edges of the matt. Any suggestions on how to tackle the problem? Short of digging in a physical barrier I am stumped.

Thanks

[MitchellMc]

Unfortunately, yes, a physical barrier really is the most reliable long term solution when you are dealing with running grasses coming in from next door @RohanMelb. Many grasses will happily travel under weed mat and then pop up at the edges, so what you are seeing is very common.

You can improve what you already have by extending the weed mat right up the fence line and even turning it up vertically against the fence as much as possible before covering it again. This can help reduce the chance of runners getting over the top, but it will not stop runners that are determined to come through underneath.

Other than installing a proper barrier, the only realistic alternative is to spot treat the grass that appears on your side with a suitable weed killer. This will kill what has come through, and in some cases it may knock back a small amount of growth on the neighbour’s side as well, but it will not permanently stop new runners from forming. It becomes more of an ongoing maintenance approach rather than a once off fix.

If you have a good relationship with your neighbour, it is also worth having a chat with them about the issue. Sometimes installing a barrier on their side of the fence, or both sides at the same time, can be the most effective and neighbourly solution.

Please let me know if you have any questions.

Mitchell

[RohanMelb]

Thank you for the reply.

How deep should the barrier go?

[MitchellMc]

The root barrier can go anywhere up to 600mm @RohanMelb. The deeper the better, but for grass, you could probably get away with 300mm.

Mitchell