There are certain plants that I think most gardens should not have. This is my opinion and to each gardener his/her own. I chose these plants for the work they create as they spread through your garden requiring you to hire someone to come control them when money could be well spent elsewhere. Here they are:
1. Liriope
It’s invasive and rarely stays where you want it to be. Often clients have us dig it all out after a few years of being annoyed by it growing into everything else. People like it because its evergreen and a nice border plant but unless you want to dig it and replant it in neat rows every few years its going to annoy you. A wise replacement would be Carex pensylvanica or glauca- also evergreen and has a similar growth habit to liriope but is not invasive and is also native (therefore low maintenance).
2. Russian sage
While I LOVE the latin name of this plant and recite it when I need to impress people with my plant knowledge (Perovskia atriplicifolia), I do not recommend planting it. This is a pretty purple plant that many people mistake for lavender that looks nice when planted. After a few years it tends to creep from its original spot into other places in the landscape/garden. It could be used in mass plantings in a bed with only Russian sage. An alternative would be catmint- I use the variety ‘Walkers Low’. Catmint is low maintenance and attracts butterflies and does not migrate the way Russian sage does.
3. English ivy
Digging ivy is doable and I have developed my own method of having one person roll the ivy back while another digs the roots out. That being said- its a big project! Ivy climbs on trees and kills them, destroys the exterior of houses and competes and usually wins over any plant it is planted near. If you need a groundcover I would recommend the native Pachysandra procumbens.
If you would like to plant one of these just use them appropriately- in a bed by themselves, away from trees or other plants that you would like to grow. Each of these will compete, and win, for nutriets, water and space in your garden.
So lighten your gardening load and plant something else!