Our group wanted to grow a woodland garden under some shade trees on our property where there currently is heavy growth of English Ivy. We were thinking of pulling out as much of the ivy as possible and then sheet mulching with layers of cardboard. Then we would add about 8 inches of compost. We wanted to plant woodland plants like ferns, wintergreen, salal, red twig dogwood, and huckleberry, and we were thinking of cutting holes in the cardboard to put the 1-gallon size pots through.
Because it is aggressive, we’re concerned the ivy may push through the cardboard. However, we were hoping that if we got good enough growth from our woodland plants, they would get established and outcompete the ivy after the cardboard decomposes.
We would really like to get your opinion if this approach would likely work?
~Mike Bald, Founder of Got Weeds?
I can really only offer three thoughts.
First, is it possible to install plants into the ivy, like using it as a suppressor of other plants? Right now, the ivy is serving to protect and cover bare ground, so if there is some energy available to keep the ivy from climbing the new plants, maybe just leave it in place?
Second, if you want to use cardboard, which I have done in various scenarios, I usually just keep adding on more. Never pick it up. Just keep adding more layers of cardboard over the space of 2-3 years. It works well if you are trying to hold the ivy behind a certain line; just progressively add cardboard in that direction. I hope that makes sense; visualize moving the cardboard line deeper into the ivy patch every spring.
Third, I like to plant in waves, so transitioning a space would involve installing clusters of desired plants every spring and fall for perhaps 2-3 years. That lets us see what’s working and gets things a little more spread out in terms of age. The worst thing for a woodland is to have everything the same age – you want diversity of species and genetics and age categories.
~Bruce Wenning, horticulturist at The Country Club in Brookline, Massachusetts.
English Ivy is a tough plant to remove, but you can do it. Yes, cut it back so you can see the ground and then pull or dig it out. If you can cover it with plywood (not cardboard), you will have better results. Keep it covered for six months if possible. Any native plants that you plant in place of the ivy will NOT crowd out or OUTCOMPETE the ivy.
Cardboard with mulch may be cheaper than wood but may not kill it in the short term. You may need to cover for more than six months with that method and monitor it for sending shoots up through the cardboard and mulch.
You can pull it out better if you loosen the soil with a shovel. Digging it out works best if you cut it back to the ground, remove the cut stems and dig out the roots. It may not be as pervasive as it looks.
~Przemyslaw Walczak, Horticulturist Chanticleer Gardens
Pulling English Ivy is very effective. Using systemic herbicide works as well.
Cardboard and 8” of compost could restrict water and air to tree roots and adds more labor.
For me, removing the ivy by pulling and following up with spot weeding was very effective.
Another possibility is to mow it very low with a push mower or scalp it with a string trimmer and pull afterward when the foliage and young twigs have wilted – a lot less material to handle, and it weakens it a bit as well.
English Ivy is extremely shade tolerant, and natives will have a hard time outcompeting it.
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