Question of the Week: January 13, 2022
“I have poison ivy growing up through my holly. How can I kill it without killing the holly? Is there a spray that will accomplish that?”
There is no herbicide that is that selective. What kills one broadleafed plant (poison ivy) would kill another broadleafed plant (a holly).
However, there is a work-around. I’ll give it to you, but first a warning you must always remember:
All parts of the poison ivy plant contain the oil that causes the allergic reaction: leaves, stems, roots, even seeds.
Now that the poison ivy has lost all of its leaves you can carefully search beneath the shrubs and clip the ivy’s trunks where they emerge from the ground. Do a thorough search. Use a piece of plywood or a 2×4 – whatever it takes to pry up the lowest branches of the holly plant so that you can see in underneath.
By clipping the poison ivy now there won’t be any leaves to wilt and turn brown – just the bare stems to die and become brittle. They will eventually break and fall to the ground. You may even be able to reach in with the lopping shears and clip them into smaller pieces to speed up the work.
Where the poison ivy has attached to the wall use a small hoe to pull the stems loose gently from the bricks or stones.
Do not touch the stems, and do not touch the head of the hoe or the blades of the lopping shears. They will be coated in the ivy’s oil. Wear a long-sleeved shirt and washable gloves while you’re doing all of this work, and be careful not to touch your face in the process.
Come spring, watch beneath the holly for sprouts that will come up from the roots of the poison ivy. Spray them carefully with a trigger bottle of broadleafed weedkiller containing a 2,4-D product. Use low pressure and coat the leaves. Do not apply with a tank sprayer or hose-end sprayer. You may have to repeat a couple of times several weeks apart, but this should eliminate the poison ivy once and for all.