Q. Two of my flowerbeds have been overrun with daylilies and spearmint for years. What can I do to start over? I love the daylilies and spearmint, but would prefer to have some other beautiful—and more manageable—plants. I do have crocus, hyacinth, tulips and daffodils coming up every year, but the daylilies take over fast. Then the spearmint takes over. I need a plan and hope you can suggest one. Thanks!
- ---Susan in Abington, PA
Then the timing should be perfect for you to cook your unloved flowers and mint away. Soak the soil well and slowly pull up as much of the adult mint as you can. If daylilies have emerged, pull as many of them as you can, also from wet soil. But even if you get all the plants out, there are probably thousands of viable mint seeds and tenacious root pieces in the soil, so we will solarize the bed clean. Level the soil, soak it well, cover it with clear plastic and anchor the plastic in place for the entire summer. Remove the plastic in the fall, and you can safely replant the bulbs (and anything else you want).
A thick layer of wood or bark mulch isn't a good alternative. It could cover your home and car with unsightly fungal spores; you'd have to give up the beds for the summer anyway; and it would not be nearly as effective as solarization, which is probably the only reliable way to get rid of these highly persistent plants. (Here's a Previous Question of the week with lots more info on soil solarization.)
Q. I really appreciate your organic solutions to gardening problems. It's great that you are spreading the word about these awful toxic chemicals that people seem to think are fine to spread around the place! We moved into a new-to-us home last November. Ivy covered the lower half of the house, had overtaken the garden and even brought down some of the fences. There are some lilacs in the middle of one of the ivy patches. I have pulled the ivy off our walls, for fear of what it's doing to the brick, and have cleared much of one flowerbed by good old fashioned weeding.
But what should I do with the large patches in the rest of the garden? I read your previous Question of the Week on ivy, so I know that herbicidal soap won't kill the waxy-leafed plants. I don't want to hurt the lilacs, but would like to have the ivy gone by the time planting season comes so I can grow flowers and vegetables. My dad thinks I should rototill the soil so it will be easier to pull the ivy. Is this a good idea?
- ---Katharine in Philadelphia, PA
Allow the lilacs to bloom, then prune them back a bit, replant them in big pots, place the pots in an area with sun and good airflow and replant them in the fall in your first truly-ivy cleared area.
And be realistic: There is no way you will be quickly rid of this highly persistent plant. Ancient ivy is as big a negative factor when considering a home as a leaky roof or failing heating system, and it's going to take as much time and attention as any other large-scale problem.
As you note, no herbicide is an option, as they all slide right off those waxy leaves. And you would have to use such massive amounts of chemicals or high strength vinegar to kill the decades-old roots that it would cost a fortune—not to mention the potential years off your life and devastation to wildlife if you took the chemical path.
Instead I suggest you divide the yard into quadrants. Pick the area with the most full sun and rope it off. Soak the ground well and pull as much of the ivy as you can. Hire some kids to help. Then surround that area with deep edging to keep the adjacent ivy at bay and cover the pulled area with a layer of heavy cardboard. Build raised bed frames overtop, fill the frames with compost and dark topsoil and plant away. The results will be sensational. Mow the rest of the ivy down all summer and collect and trash the "clippings".
Every year, clear a different area and build more raised beds in those spots. The mowing will weaken the root system and make the work easier each successive season. When all your beds are built, lay cardboard over the remaining ivy areas, cover these walkways with stone, pavers or other non-wood material and the ivy will be nothing more than a bad memory.