I do it all by hand, Gail. There is no where in my area to rent tools. Around here you kind of have to be the mother of invention on a lot of plans. I installed some similar edging for my mother several years ago, the black rubber kind and decided that is a job I am never doing again so do empathize with you on your project. Trenching first really sounds like the way to go so that you can get everything in nice and straight and even. Good luck with the project!

MeMo

I do mine by hand. I always tackle things a bit at a time so it's not too hard on the body.

That might be a big enough job to get rent a tool. I have a hand tool, called a Cobra that I use to break up the nut grass which looks very similar to your quack grass. But You are needed fairly even edges...what about an automated trencher? (I mean renting a mechanical trencher.) DH is talking about renting one so he can run power and water to my shed. Think about it. I think you need mechanical help there.
kay

Big job = Big tool

That's my philosophy.

If you haven't used an excavator or backhoe before, I'm sure you'll have fun learning.

ThinMan

I'm not quite clear from the pictures what you are trying to do there. I don't know the full extent of that flowerbed but it looks to me like a candidate for starting from scratch rather than trying to put an edging in post hoc. To be brutally honest it's hard to see which side of the edging is the bed. It doesn't appear to have much in it except a few shrubs, some bulbs and a lot of grass so I think I'd be tempted to dig out all the plants I wanted to save and put them aside, maybe on a tarp with soil mounded over the roots and kept moist. Then I'd thoroughly prepare the bed, by hand with a fork, not spade, removing every morsel of grass and making a good sharp edge with a spade or edging tool. At this point you could insert your artificial edging strip. Then I'd get the plants I'd removed and remove every bit of grass from the roots. Finally I'd replant in the new bed. It's a big job but I really don't think you'll ever win against the grass by picking away at it and trying to work around the plants in situ. In the long run I think it would give you a better result and save a lot of work in the future. The edge will need keeping trimmed with edging shears to stop the grass crossing the slit trench and getting back into the bed. Good luck!

Has anyone used a Black and Decker Edge Hog? I saw it recommended somewhere a while back and found one at Home Depot. I have been edging my beds by hand with the half moon edging tool. That is getting too be too much but would like to keep the trench edges.

I will say that you should go for a tool rental, this seems to be a big enough job to go for it. You will be paying good money to rent it but you will have fun time selecting an excavator and using it, if this is your first time.

My Son does run trencher for big construction Co. I forgot what he said new one cost. It was lot of $$$$.

$206 for the excavator
1 day's wages since you are taking off.
Add those up and see maybe can you find a service that will do it for you.
I'm not talking run of the mill lawn mowing companies, but there are garden companies that do projects. If you have a subscription to Angie's list you can scope out reputations and costs.
Maybe a service might be too expensive but who knows?

I'm wondering as flora, by "trench edging" what exactly do you mean as far as in your photo? What is the sheet metal, is that your edging material? I think you'd be better off doing it by hand rather than renting an excavator to do edging. Do you have any books for reference on edging flower beds, some photos to give inspiration?

Did you last 4 posters realize you are responding to someone who hasn't been to the thread in a year?

Not until you mentioned it mytime and I went back to check the date of OP - ha! Oh brother. Well, I wonder what happened with the trench edging?

LOL ... Mytime, I thought that photo looked familiar. Since I was curious I looked for other posts by the OP. Only found 4 on this forum. Here's another with the same pic. Wonder how things turned out?

Here is a link that might be useful: other thread

I was also wondering how it turned out, because I was just trying the same thing. But my husband came out and laughed at me, "Honey, that's not going to stop those roots...they'll punch right through!" So he cut some corrugated roofing for me...it's been used so has holes in it, so it's doubled, tripled, quadrupled even in the over lap seam area. If the aspen, cottonwood, rose, raspberry, viburnum, fireweed and horsetail make it through, I give up and he can have the area back for lawn. Got to say, it will be the best lawn in the yard with all the amendments to the soil I put in. But if all you're trying to stop is grass, it should work really well...overkill, I'd say, and sharp as all get out, so the top edge has to be finished or somehow protected.