This spring, I set out to answer the question --- is there a fast no-till way to eradicate overwintering weeds in a month or less? A tall order, I know, but my slow-and-sure kill mulches don't work for a lot of gardeners because they aren't able to think ahead to prepare the soil a few months before planting. The photo above shows four experimental beds (and a control bed that's simply been weed-whacked repeatedly) attempting to answer that question.

Option A involved a type of very thin, biodegradable black plastic. The photo above shows Kayla helping me lay down the plastic three weeks ago. The photo below shows completely dead oats underneath the plastic this past Thursday.

This product worked much faster than I thought it would, probably because we've had crazy summer weather in April and early May (highs up to 90 some days), which surely heated up the soil underneath very quickly.

On the down side, all it took was Huckleberry walking across the plastic to tear little holes, which a light wind quickly turned into long tears. (I'm telling you Huckleberry really isn't that big of a cat!) So, although effective, I'd caution against using this product anywhere that pets will be walking even a little bit.

Option 2 was solarization, which I explained in more depth in this post. The solarization worked about equally as fast as the black plastic, with the bonus that this clear plastic didn't shred after light pet traffic. The clear plastic also held in the soil moisture, which was handy since rainfall for the last few weeks has been nearly nonexistant.

The downside of solarization is that my raised beds in this area are tall enough that the north-facing side of the bed didn't heat up fully, so the oats underneath the plastic on that side are still somewhat green. So if you plan to use solarization to prepare soil, you'll want to stick to areas where the ground is as flat as possible. With that caveat and assuming hot weather, you can also plant into solarized ground in about three weeks if your weeds are only moderatly tenacious. (Add a few more weeks for both Option A and Option B if you're trying to kill a wily perennial like wiregrass.)

Option 3 was a storebought roll of paper mulch. This mulch was the least effective as a fast weedkill, although it looks to be the most effective as a long-term ground cover.

As Mark mentioned, the first rain bleached the dye out of the paper, and the lighter color left behind meant that the mulch simply acted like a barrier between the weeds and the sun rather than heating the soil underneath. The result is that the weeds beneath the paper mulch aren't quite dead yet, although the paper is still providing a good barrier around the high-density apple trees. I suspect I'll need to wait about 4 to 6 weeks between laying down this mulch over an oat cover crop and planting into the bare soil.

As another downside, Lucy running across the mulch did poke holes in the paper layer, allowing some weeds to come up through. That said, the paper has much more structural integrity than the very thin black plastic, so only the paw-print areas were affected rather than the whole sheet of mulch. So I'd say the plastic mulch is acceptable over areas with light pet traffic.

Option 4 was mad of entirely free materials, but I didn't lay them down until later than the previous options and thus don't have a comparison yet to the other methods. Kayla's father came through with a big box of newspaper (thanks, Jimmy!), and I've been applying the sheets using different methods in different parts of the garden.

The photo to the left shows how I laid the paper down dry and then anchored it with deep-bedding material from the goat coop. Unfortunately, some of the sheets have blown away, which is why I started soaking the paper in a bucket of water before applying.

The top photo in this section shows some newspaper-mulched areas around the hazelnut bushes. Since I have comfrey plants growing along the aisles in that part of the garden, it was easy to yank handfuls of the greenery as a short of chop-'n-drop to weigh the wetted newspapers down. I'll post a followup in a few weeks once I know more about how the newspaper mulches compare to the other methods, but my guess is that they'll be comparable to the storebought paper mulch.

The final method I'm trying is a more long-lived type of black plastic that is supposed to be good for 12 years (assuming you don't puncture the fabric in the interim). I laid down an experimental span in the proto-tree-alley a week ago, with the plan of taking up the plastic at the end of the month and planting sweet potatoes there. I'll keep you posted about weed control there as well.

Phew! I know that's a lot of data, but I hope it'll help you decide on a weed barrier that'll fit your particular garden needs. And perhaps there's another method I haven't considered that you've used with success in your garden? Be sure to let me know in the comments!