Cardboard layer

Asked May 17, 2020, 6:13 AM EDT

If I am filling a raised bed with 10 inches of soil do I need to lay a layer of cardboard over the bottom? We dug up the grass, but should I also place cardboard over the bottom? If I am growing tomatoes will the roots be obstructed by the cardboard before the cardboard breaks down? Thank you for any help.

Maryland

6 Responses

Hi- you do not need the cardboard layer, especially since you removed the turf. If you do this again, you can cut the turf very low, cover with a layer of cardboard and then the 10 inches of soil. That way you don't have to dig up the turf- it decomposes in place naturally. Unwaxed cardboard will break down in 1-2 months in later spring and plant roots can grow through it, when it weakens sufficiently, into the native soil.

If you decide to put the cardboard down now and plant, your tomato plant roots may be constricted, especially if they are large.
Jon

Thank you again. Yes, will definitely be doing this again. Yes, Digging up turf is harder than I realized, but starting a raised bad has still been a lot of fun. My dad wanted me to put this together on short notice and so I’ve been try to scramble for materials and to figure out what I have to do. Next year I will save all my leaves to try and compost. Here’s the stacked stone bed with a bit of the leafgro, more hopefully to be delivered soon. Although next year for a 2nd raised bed I think wood is what I’ll do. Thanks for answering these questions I wish I’d done this years ago.

Thanks for sharing the photo. A truly unique raised bed!
Jon

Thank you! Although I think I made a mistake. I put the leaf gro Leaf compost soil conditioner down yesterday Because I was waiting for the soil to be delivered today and didn’t Want to leave the soil bare after digging off the top of the grass. But today I got a lot of flies. And looking it up putting so much organic matter down on the ground and wetting it probably attracted the flies. Any advice on how to fix it?

Hi- lots of different types of insects are on the move now- emerging from overwintering, swarming, mating, etc. Some species lay their eggs in organic matter. The flies, regardless of species, are harmless and will not affect your garden.
Jon

Great, thank you so much.