Weeds growing through rock bedI

[maros91]

I just completed a landscaping project in my front yard complete with edging, plants, 2 trees, river rock, and an old piece of farm equipment. I placed fabric on the ground before placing my rock and now after 3 weeks there is weeds growing everywhere through the fabric. I want to know whats the most lethal stuff to put down to kill the weeds but not kill my plants. I,ve tried the weed and grass killer in the black and green bottle but didn,t work. Whats the most lethal stuff?

[echo2010]

Preen

[Tom7227]

a blowtorch

[MuleShack]

Did you put the fabric down over weeds and/or grass when creating the bed? If so they will tend to grow thru the fabric the first year unless sprayed. If you put the fabric down over dirt, then there shouldn't see any weed growth...unless you got a screen mesh for fabric.

If you did put the fabric down over weeds and they are growing thru, then a simple round up spray carefully placed on the weed leaves and not pooled should do the trick with out killing the good plants. Get the round up that says rain proof which has a sticker in it to adhere to the leaves so it wont run off into the soil and harm the good plants.

On a side note, it may be that your river rock is not dense enough where sunlight and air can get to the ground yet to promote growth instead of smuthering it out. It is best to have 3" of rock to keep the sunlight out and that help to prevent future growth.

Kill the existing weeds with a round up spray and then use the preen product to prevent future weeds.

[DRH1175]

Are they growing through or on top in the rocks. I just had my yard professionaly installed in june and had the same probelm. The weeds were actually on top. I sprayed them all with roundup. Then applied a nice thick layer of preen everywhere. Each year I will be applying preen in she sping and mid summer. Fabric and rock help controlling weeds. but to be weed free it still takes a little work from my experience. Also did you overlap the seams on the fabric.

[LwnmwnMan2]

Preen works okay, but if you look for a product called "Snapshot" it will last all season with one application.

It can be found at the same location I and others have mentioned before.

Also, as Preen, Snapshot only works as a pre-emergent, not a post emergent.

Spray the weeds that have already emererged, and put down your pre-emergent chemical of choice. It's a granular that can go right over the top of most established plants.

If you're concerned about spraying the roundup, grab a pail, or 5 gallon bucket to put over whatever plants you're looking to keep so you don't risk overspray, if you're not confident in your spraying abilities.

[maros91]

The weeds were growing right through the fabric. During my project I used a sod cutter and took out the top layer of grass/weeds and put my fabric down. I did overlap about 3 inches. I only put down enough rock to just cover the fabric, maybe a little deeper in some spots so I am sure sunlight was still getting through. Long story longer I am pulling up the rock and the fabric (cheapest stuff you can buy I might add) and am going to dig the weeds out and spray with round-up. Then I am going to through in some Preen then a layer of the cheap fabric and then a layer of some better fabric and then add more rock (at least 3"). Maybe this will do the trick. I should have did this in the first place but I guess now I know. I will see if I can take some picks and post them.

[LwnmwnMan2]

You don't have to do that much work Biff.

Just pull as much as you can / would like right now, and then spray the rest.

Put some Preen over the top and you're going to be good to go.

There's a good chance that you'll still get some growth of weeds from the ones that have already started to germinate from earlier, but just spray / pull those when you see them.

Add some more rock as your budget allows.

There's a fair amount of landscape beds out there that have ZERO fabric, the weeds are just controlled chemically and manually.

[maros91]

Will the Preen go through the rocks and into the soil?

[LwnmwnMan2]

Will the Preen go through the rocks and into the soil?

Yes. Preen, Snapshot, Treflan or other products will work by just spreading or shaking the product right over the top.

It works the essentially the same way as a pre-emergent does for crabgrass, in that it prevents weeds from germinating.

When it rains, or if you have irrigation (not drip line) it will push the product down to soil (or rock level) and start to break the pellet down to form the barrier.

One of the discussions on the lawn / landscape websites is do you put it down before the rock / mulch, or go over the top.

I personally like to go over the top, since if you put it down first, you run the risk of moving it (although unlikely) or you run the risk of introducing dirt (sediments) with your rock, or if you put mulch down, there could be some weeds that grow from the mulch.

If you put the product over the top of everything, then you are preventing weeds from these sediments or from the new mulch that was placed.

[maros91]

Nice. Great info!!! I will quit tearing up the project and just kill the weeds I see with Round-up and pull them and sprinkle the Preen in. Good stuff LwnmwnMan2 and everyone else. You saved me many hours of work and cussing and swearing.

[larryz]

I showed this post to my wife as we are having some of the same problems. Her questions were can you use this Preen product in a perennial garden and will it have any effect on getting spreading plants to promote new growth of plants?

[LwnmwnMan2]

"Usually" once a plant has rooted, it will not affect the plant. If the plant spreads by root structure, you should be fine.

All of these products will have labels on them, and what plants not to use them on, so just to be safe, I would recommend reading the label, as with any chemical product.

Most of these you can google the product name and find a label, read it at home, so you're not standing in the aisle at the store, trying to squint, hold the bottle at a certain angle, get better lighting, etc., to try to read all the fine small print of plants.

For others that are following this thread, and are thinking "HEY!!! what about gardens???!?!" these products are NOT rated for food stuffs.

I'm not entirely sure, but Preen MIGHT have a food rated product, but the others are not.