At War with Mother-in-Law’s Revenge

When we first moved in, Kay, the previous homeowner, came to pick up some mail and offered some gardening tips on how to care for all the beautiful perennials she planted in her 40 years in the home. One of the first things she said was that I needed to pull the “mother-in-law’s revenge” early and often.

What’s mother-in-law’s revenge, you ask? Well, Kay didn’t really know what it was but she named this formidable garden invader after her mother-in-law gifted Kay a few seedlings for her garden claiming they’d be the perfect filler and ground cover for her beautiful front gardens. Kay’s mother-in-law passed shortly after she planted them and said they’ve been haunting her gardens ever since. The seedlings quickly multiplied and choked out many of her strongest plants. She’s been pulling them from her garden–and cursing her mother-in-law–every year since.

Since making this our home and taking over the gardens, I too now curse Kay’s mother-in-law every time I have to weed it out of the gardens. It doesn’t just cover the open, available real estate on the ground, it likes to hide in the middle of other plants–like my hostas, chrysanthemums, and russian sage–making finding them early and pulling a bitch. And despite my best back-breaking, weed-pulling efforts, it seems to come back with more vehemence each time. I’m telling y’all this stuff could flourish in a vat of bleach with no light.

Finally, I did some research last year and discovered the real name of this pest–goutweed. Goutweed is an extremely aggressive, invasive perennial. Savvy Gardening calls it the “cockroach of the botanical world” and “a beast to eradicate”. While on the prohibited or restricted plant list in some states, goutweed can be found in some garden centers under the name of “bishop’s-weed” or even “snow-on-the-mountian”.

Turns out, Kay’s approach of pulling the plant, which often comes up fairly easily, is one of the worst things you can do! Goutweed stems from a web of rhizomes which branch far and wide underground. You see, rhizomes have a nasty habit of multiplying from broken or left behind roots in the ground–like when you pluck gray a hair and five more emerge, thriving and taunting you.

So how do you get rid of it? It’s a painstaking process. Many sites recommend fully covering it with plastic, essentially “cooking” the devil which can take anywhere from 8 weeks to 2 whole seasons. You can also smother it by cutting it down and covering it with cardboard and mulch – 2-3 feet beyond the menace’s prersence. Another option is spraying it down with a vinegar solution or even chemical-based weed killer like Round-up.

My initial plan was to try the smother and cover method. I figured I could cover around some existing plants and add good soil above, building up the gardens and planting new perennials which would look better in the front of the house than black plastic. Besides, I had PLENTY of cardboard thanks to Amazon and Christmas time which I stored for several months. Unfortunately, when we prepared for hosting my sister-in-law’s engagement party in May, Sr. wanted the garage clean and recycled all my cardboard. To be fair, I caved and gave him permission.

June is always a busy month at work and difficult for me to get in the gardens and then I was out of comission for several months with nausea in my first trimester. By the time I got back to life–and the gardens–in September, mother-in-law’s revenge had ravaged the front gardens.

Exhausted and over it, I’m not ashamed to say I finally caved and turned to the chemicals. After all, this was war. I came to terms with the fact that there’d be some casualties, like my russian sage, mums, and a few other perennials. After the first careful spray, I was disappointed that the beast didn’t begin to wither within hours. I had totally imagined a scene out of The Wizard of Oz when Dorothy douses the Wicked Witch with water and finally ends her reign of terror.

No such luck. However, after a few weeks a difference could be seen. AND my chrysanthemums didn’t die! Two more rounds of spraying and I’ve made a serious dent in the rein of Kay’s Mother-in-law’s revenge.

Unfortunately, the arrival of the cold weather has stalled my progress because the chemical sprays are recommended for using weather above 60 degrees. Looks like there will be more work in the spring. I’m thinking I may need to srpay again a time or two and then will likely cover with cardboard and fresh soil so I can plant a few new beauties. This will allow the new plants to thrive while the chemicals dissipate under the decomposing cardboard barrier.

I also haven’t touched the bed of hostas in front of the kitchen bay window yet but I plan to smother and cover that small bed. With my Japanese Maple in that bed, I don’t want to use any chemicals. Besides, the hostas are overgrown and can’t be divided because they’re infested with goutweed so removal or covering is the best option. I’ll cover it this winter and it’ll be fun to design a new perennial bed there in the spring–something that doesn’t have hostas maybe?