6

Solarization is a combination killer by smothering and intense heat. This may work to kill your crabgrass, but some of it may still survive even this harsh treatment. Crab grass may even grow through the plastic if you don't get thick enough plastic. I can't think of any long term drawbacks from an organic point of view, but the soil underneath will be made ...


5

I can't think of any easy solution to this problem - what you're doing already, that is, trenching and keeping the trench clear, is probably the best idea. Laying lime and adding sand on top just means the sand will blow everywhere if you use any kind of hover mower, and you'd have to very carefully collect any clippings off the top of that loose sand ...


4

The pre-emergent used in that product is Pendimethalin (3,4-Dimethyl-2,6-dinitro-N-pentan-3-yl-aniline), and its mode of action is microtubule assembly inhibition in very immature plant shoots (In other words, it inhibits microtubules, the structures which pull cells apart in cell division (mitosis), thus shutting down growth). This is the same mode of ...


4

I come at things form an organic landscaping background, so we don't go for pre-emergents, which would prevent it from germinating next year. With that in mind, your goal is to grow the the turf grass thick enough to keep crabgrass from germinating and growing next year. If your soil is bad, you'll want to address that. Have it tested by a reputable lab ...


4

Nothing can beat a thick lawn, mowed high, to choke out and starve weed seedlings from growing, but it can take a while to get your lawn to that point. Overseeding is a great way to do this. I dormant overseed here in Ohio in late December and let the freeze thaw cycle help pull the seeds into cracks in the soil so that when springs arrives, I get good ...


3

I have dug trenches everywhere between the edges of the landscape beds/walks and the lawn. This does get tedious, but next time I am going to dig a trench deep enough to lay down galvanised square gutter to keep the edges. Then I will fill the gutter with stones to weigh it down and provide an edging that I can easily maintain.


3

As you can imagine, the topic of crabgrass has come up a number of times before in this forum. A couple of highly voted answers which may be relevant to you are this one and this other one. Crabgrass becomes quite obvious at this time of year - for most of the summer it remains sort of green filling in patches but then turns a kind of purplish red colour ...


3

I agree with Randy that a soil test is essential but a few simple tests now will help guide your decision: go to your lawn and dig a few holes and take a cup sized sample from each when the soil is neither really dry or really wet take the sample in your hand and make a ball of it. Does the ball crumble apart when you open your hand ( sandy) or sit like a ...


3

The time out period will be listed on the label but is commonly six weeks or more. With the climate changing quickly and causing ground temperatures to rise you have to be diligent to apply at the right time, too late does no good. From this professional in Georgia Crabgrass seed, you see, germinates when spring soil temperatures tend upwards from 50 ...


2

Corn gluten meal (CGM) which is a byproduct of some corn processing methods and can be attained very cheaply in a raw form from a grain mill, or purchased for quite a bit more money as a “natural / organic crab grass preventative” is a great choice. Crab grass is an annual and thus controlling it in my zone (Ohio) usually happens around the time the ...


2

I wonder if you topsoil was removed? Possibly even sold to someone else. Regardless, it seems as though your topsoil is not what topsoil should be. You may start with a soil test. Here is an especially bad report I found online that I'll use for illustration purposes. Not much of anything would grow on this "lawn", except a few weeds here and there. It ...


2

Re the flowerbeds, yes, you need to dig them over and extract all weed roots, preferably without leaving any behind. The guy at Home Depot's advice was incorrect though - if you want to use Round Up, that works 'through the green', which means it needs to be applied to strongly growing green growth when the soil is damp. Applying it to roots or bare soil ...


2

If your lawn is almost ALL crabgrass then glyphosate or roundup is indicated. This is absorbed by the foliage and taken down into the roots where the KILL happens. Takes at least 3 weeks. Perhaps a second application. Read that label 5 times I kid you NOT. That is what they taught us as Pesticide Applicators. Five times!! Do not spray in any wind, ...


1

Two things to consider here: the type of soil close to your hard surfaces and temperature and humidity in the two microclimates. Basically nature is just doing its job here, selecting the most appropriate plant material for the location. Crabgrass likes hot and dry conditions where there is no competition from other grasses and plants and drainage is good. ...


1

Instead of trying to kill the weeds as is, you could think of them as future fertilizer. Get some cardboard or newspaper, lay it on top, and start "lasagna gardening" by putting compost on top of that. You'll be able to plant in it come spring. One thing I've learned from weeds is that you can try to go down to their level, but you end up opening up the soil ...


1

Cool season grasses are far easier to control weeds just by the height of the crop and training the roots to grow deeply and be drought tolerant. You don't have that ability. Spring pre emergence seems to be the best 'control'. How big is your lawn? How infested is your lawn with crabgrass? I would be more inclined to do very surgical removal using ...


1

For your lawn: You can use a selective herbicide to target the crabgrass. Make sure your product is safe to use on Zoysia. I use Quinclorac based herbicide, because I find that Zoysia is highly resistant to it, once established. I know of some people who use Monosodium methyl arsenate (MSMA) based herbicides, but if you do that, be careful, because some ...


1

I am glad you asked us rather than listen to True Green and Home Depot. My goodness! Please PLEASE forget that plastic membrane!! Please. It is one of the dumbest things us humans have done...I've made tons of money ripping this stuff out. It causes far more headaches and does zip for weeds. Any mulch like bark mulch should be as fine as you are able ...


1

I've had years of experience with 'lawns'...the grasses I am familiar with are lawn grasses that do well in the northwest. From your picture, which looks oh-so-familiar, I would do one of two things: #1. Aerate, pulling plugs of soil out of your lawn and leave the plugs on the lawn; edge your lawn using a weedwacker or metal-blade edger between concrete ...


1

There are several modes of action in pre-emergent herbicides, but they all have one thing in common, which is targeting young, immature plants that are still dependent on the parent seed. From my answer here: I'd wait until the 3 leaf stage (where most of the seedlings have 3 blades each). This will ensure that they are finished taking nutrients from ...


1

It's tricky dormant seeding and then waiting for seed to germinate to put pre-emergent down. If it is warm enough for the new seed to germinate, it's warm enough for crabgrass to do the same. A product such as Tupersan can be applied to prevent crabgrass without preventing the grass seed from germinating. It is expensive and only lasts for about 30 days, so ...


1

Have no fear my friend, I have your solution: Tenacity I have been able to battle the horrible lawn in my foreclosure, located in Ohio, with weed-b-gone fairly well. Winning that battle, along with dormant overseeding with the wet springs here, I turned my lawn into a gem of the subdivision. However, the crabgrass and quackgrass is nuts. The big box ...


1

Believe it or not, baking soda does the trick. It is usually best to spot treat as soon as you see some crabgrass as it spreads very fast. Especially in the hot summer. You still have to pull the dead crabgrass root and all once it dries out or it WILL come back. Crabgrass is the bane of my existence and I have fought this losing battle for many years now....


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