How to kill the grass and weeds before put down mulch?

Saltwater

 I want to put down mulch under the trampoline as grass just doesn’t grow here - soil is bad, too much rock and too much shade. I’ve put a tarp down to kill the grass and weeds. Is there anything else I can do to Kill them before digging them up? I don’t want to use roundup as the kids play here.

Would vinegar ruin the soil and prevent me from growing plants here again in future. I intend to make this a fun nature play area for little ones so don’t want to use any herbicides. 

Should I put anything down before Laying mulch to prevent weeds from returning?

MitchellMc

Hi @Saltwater,

It sounds like the perfect opportunity to use weed matting. No need to dig the weeds up; just lay the matting down before your mulch. I'd suggest bordering your mulch with garden edging as it will prevent the mulch from being kicked out of the area and onto the grass by the children. It will also make it easy to mow and edge up against. So it doesn't become a trip hazard, you can dig the edging partially into the ground.

Vinegar would break down relatively quickly (under one week) and won't prevent you from planting in the future. Richgro 3L Beat-A-Weed Natural Weedkiller would also be another child-safe alternative to glyphosate. You don't want them rolling around in it whilst it's wet, so keep them off the area until it dries.

Please let me know if you have any questions.

Mitchell