Should I start from scratch with my flower beds? And if so, how?

June 18, 2015 11:13 AM

My flowerbeds are overrun with weeds, no matter how much I pull. Should I start completely over, and if so, what's the best way to do that?

I have a few raised flower beds in my backyard - they were installed by the previous owners of my house, which we bought about two years ago. They are in a really great location that gets a ton of sun so I usually plant stuff that does well in the sun, like tomatoes.

However, they are constantly, constantly overrun with weeds. I've mulched, I've put down straw, I've pulled a whole bunch by hand, and they still keep coming. Every time I clear out a bed, it's like two weeks later and the weeds are back and even bigger. (Probably not in reality, but it sure feels like it). They attract bugs and some have popped up that I Googled and they are poisonous (I have two little kids).

I'm wondering if I should scrape out all the soil that's in the beds and use fresh soil. Or maybe something else? I'm not much of a gardener - I buy seedlings from a local farm and I'm able to plant them and water them, but that's about it. And if I did remove all the soil and replace it, what do I do with the old soil?

posted by sutel to Home & Garden (9 answers total)

Get some black felt paper used for putting under roofing. Cover the entire garden space like lining a drawer and when happy with that, cut openings to insert your plants, then cover the paper layer with bark or mulch. Weeds are stopped and the black heated layer due to the sun hitting the felt will compost the plants you cover up and provide a rich place for good insect and worm lifestyles. Any new weeds will start then on the top where the removal effort is zero.
posted by Freedomboy at 11:38 AM on June 18, 2015 [4 favorites]

Solarize with black plastic sheeting.
posted by cecic at 11:38 AM on June 18, 2015 [1 favorite]

Best answer: I would dig up & replace the soil if it were me. It will be a bit of work but you'll almost certainly get better results. I would bag & pitch the top 6 inches of soil then spread the rest over the lawn. If you're concerned with contaminating your lawn or other beds, throw all the old soil out, in compost bags partially filled so the trash collector can lift them.

When you have the raised beds dug out, add a 2-3 inch layer of pea gravel to the bottom before you add in new soil, it will help the beds drain well & avoid fungus, mold, etc that may be contributing to your current problem.

How tall are the beds? You may need quite a lot of bagged potting soil. I buy mine from my local Costco, they carry massive bags of Miracle Gro brand. This year they went w/Miracle Gro organic potting soil and it says it contains compost. It smells strongly of fresh manure to me so I can't recommend that if it's carried in your area; you'll know if it's the same product if you can smell it in the display area of the store, it's that strong. Manure that fresh burns plants in my experience.
posted by RichardHenryYarbo at 12:14 PM on June 18, 2015 [1 favorite]

Best answer: Just FYI re landscape fabric/sheeting:

The myth of landscape fabric

Why I hate landscape fabric

More here.

I would replace the soil as well. More difficult but better results.
posted by longdaysjourney at 12:21 PM on June 18, 2015 [2 favorites]

Best answer: I had a similar problem in my garden beds (not raised ones, though), and I found the method in Weedless Gardening to be effective. Basically the method laid out in the book is to cover the existing soil with paper, then mulch it generously with layers of organic matter to smother the weeds. The book recommended using newspaper, but since I haven't seen a newspaper in years, I used contractor paper, which comes in big rolls from Lowe's/Home Depot/your local equivalent. It was not 100% effective. Even so, the number of weeds in the garden is considerably reduced and those that have sprung up are few enough to be pulled by hand.
posted by Lycaste at 12:43 PM on June 18, 2015

Have you tried using a hand hoe? They can make the act of weeding quick work if you have your plants in neat rows.

I didn't understand what hoes were actually for until recently and god damn, using one correctly made weeding much easier.
posted by Ferreous at 5:27 PM on June 18, 2015

Weed seeds are usually airborne. You can't stop them you can only manage and control them by frequent weeding or herbicides. Comopost and mulch can often be contaminated with weeds (and sometimes pesticides/herbicides).

Farming ain't easy!
posted by srboisvert at 7:04 PM on June 18, 2015

I've read about a method of "starting over" involving a layer of cardboard, a 4" layer of compost, another layer of cardboard, and another layer of compost, covering that with landscape fabric, or more cardboard with rocks on top and letting it sit for a year. I haven't needed to do it, but it seems reasonable and like it wouldn't kill your soil.
posted by cmoj at 1:51 PM on June 19, 2015

Best answer: Weeds happen. The reason the weeds come back after you've pulled other weeds is that weed seeds can lie dormant in the soil for years, and your latest weed-pulling exposed them to sunlight so they could germinate. But you don't want a sterile soil in which weeds won't grow! Keep your existing soil but add a layer of compost to rejuvenate it. You have to nurture your soil structure and its organisms, and getting new soil won't do that.

I use various methods - mulch (the strawberry bed gets last year's ornamental grass, landscape fabric between the tomatoes and peppers, and everywhere there is no grass, ornamentals, or vegetables, I cover with several inches of wood chips) and hand weeding, mostly. The "lasagna" method is great for creating new beds, but you'd basically be starting over.
posted by caryatid at 9:07 AM on June 22, 2015