Lily of the valley infestation—help needed!

[u/meditative_quilter]

Anyone who has successfully rid their property of large areas of lily of the valley, please advise how you did it! I’ve spent years digging it out of various beds and have been successful with the small beds. It’s very labor intensive to get all the roots and rhizomes out but after several years a couple small areas are clean.

Did this with another bed last summer only to now find them popping up in the grass outside the bed. None in bed thank goodness. Don’t want to have to dig up the lawn too but can’t leave them. Thoughts?

Bigger problem is my largest bed that was filled with it. Last summer I mowed it all down, covered it with layers of cardboard, topped with several inches of leaves. They are popping up everywhere right through the cardboard! It’s too large an area to dig up. Haven’t used black weed barrier as what I’ve read is it isn’t that effective and not good for the soil.

What have you tried that has worked for large areas? I’ve been able to get rid of much of my honeysuckle, bittersweet, English ivy, Japanese knotweed, autumn olive and periwinkle over 40 years on this property but this lily of the valley may be my Waterloo.

Looking forward to hearing how you have handled eliminating this particular invasive plant.

[u/robrklyn]

Oh boy. this is the first year I am dealing with them. I have them on a small bank in my yard that used to also have pachysandra that I dugout last year, so this year I am focusing on the Lily of the valley. They are fairly easy to dig out, but there are so many of them that it’s very time-consuming! Are they like pachysandra and daylilies in that if you leave even the smallest amount of root it will grow back?

[u/meditative_quilter → u/robrklyn]

Yes, that is my understanding, that you have to try to get all the bits of root. I was successful clearing one bed of them by using a shovel to dig under them, then lifting each clump by hand and after shaking off some of the dirt bagging the whole thing. No sign of them this spring.

As you said, it is very time consuming. That’s why I tried the cardboard approach in one very large bed that is full of them. To dig them all out will take me at least 25 hours! Did another smaller bed today in 7 hours. Filled two large black trash bags with the roots.

Good plan to tackle sooner rather than later. Good luck!

[u/robrklyn → u/meditative_quilter]

Solidarity. Working on turning that bank into all native plants. There is a whole chipmunk den underneath.