November Vine of the Month-Boston Ivy
In lieu of a shrub, this month we highlight a woody vine.
Want a fun way to spend an entire afternoon? Open Google and type “Are climbing vines good or bad for your walls?” If you like to avoid conflict and confrontation, you won’t like the results. I’m not sure there is a more controversial and heated topic when it comes to plants.…even more aggressive than natives vs. non-natives since we are extending outside plant-geek circles and national borders here, and EVERYONE, from plumbers to used car salesmen, seems to think they are experts.
What is one to do with so much contradictory information? Here, we have another occasion that calls for RESEARCH. Try to dig past the forums and other opinion/comment-fueled sites to knowledgeable sites from universities and botanical gardens or actual professionals in the industry who have experience AND are up to date on recent findings and studies.
Controversy aside, here’s a “Vines 101” that many commenters on forums or social media don’t realize. Most vines grow either with aerial roots (English ivy), by twining (wisteria) with tendrils (grapevine), or with little suction pads like Boston ivy. Depending on your structure, be it plaster, brick, stone, or siding, you want to choose your vine carefully if choosing one at all. Consider things such as mature height, speed of growth, evergreen vs deciduous, and flowers or fruits. I consider ALL vines high maintenance, whether on the ground or on a wall. If you do not have the time to prune once or twice a year ON A LADDER WITH SHARP TOOLS, romantic, vine-covered walls might not be the best choice for you.
The vine that covers my home is the same one that covers the walls of Wrigley Field in Chicago and numerous universities in the US and the UK: Boston ivy, Parthenocissus tricuspidata. This member of the grape family is deciduous, meaning it loses its leaves in the fall. The fall color is outstanding, and it’s easy enough to remove or trim, or it can eventually reach 50′ high quickly. Insignificant greenish-white flowers in spring give way to blue berries in the fall. Full sun is preferred for the best fall color, but it will grow just as tall and fast in shade. I chose this vine because not only does it provide that romantic, old-world look my English Tudor Cottage Revival home calls for, but it also has outstanding fall color and is deciduous, shading my walls in the summer, exposing them to the sun in winter much like a well-placed deciduous tree would on the south or west side of your home. Boston ivy uses adhesive disks like little suction cups that release a fluid that dries into a strong bond that supports the vines, so THERE ARE NO ARIAL ROOTS TO WORK INTO YOUR MORTAR.
Unlike English ivy, which uses invasive rootlets that can damage brick and wood, Boston ivy’s adhesive discs don’t damage the surface they’re attached to. However, removing the plant from painted surfaces can cause damage. I repeat Boston ivy does NOT penetrate brick mortar like English ivy can, and that only happens if your tuckpointing is shabby.
Ivy-clad walls require a high level of maintenance. Harvard, one of the “Ivy League ” schools in the US, removed its English ivy from its famous walls in 1982 after reporting spending $50,000 annually to keep it trimmed.
Which brings us back to that vines vs no-vines thing…
During my days at Missouri Botanical Garden, the RHS (Royal Horticultural Society) in the UK was the top authority on anything and everything related to plants and gardening. Although we Yanks can hold our own when it comes to horticulture these days, the UK and other European countries have been living and working with this vine topic long before our country was even founded and have done studies to prove their standings.
Check out this great video about Boston ivy for walls from an RHS expert here: Autumn colour inspiration from RHS Hyde Hall’s Boston Ivy | Grow at Home | RHS
If you are thinking, “What do THEY know,” here’s another link from Oxford, that little university across the pond that’s been around since 1096…
https://phys.org/news/2010-05-oxford-ivy-walls.html
What I love about this plant;
-Outstanding fall color follows beautiful glossy leaves.
-Ability to quickly cover walls WITHOUT damage.
-Deciduous, so it will provide shade in summer on walls, lowering AC costs.
-Unique history.
-Deer tolerant.
-Black walnut tolerant.
-Tolerates poor soils.
-Quick to cover old stumps or hillsides.
What’s not so great;
-Controversial.
-Being deciduous can be a con if you prefer evergreen ivy. The leafless stems can be unsightly in winter.
-High maintenance. Requires regular pruning at least once a year to keep away from windows, gutters, etc..
I trim or train my Boston ivy regularly to keep it off my roof, away from the plaster parts of my home, and keep my husband happy. On sound masonry, the vines are easy to remove without damage. If any adhesive discs are left behind after removal, a paint-scraper is beneficial for removing them easily and can be attached to a pole for higher situations.
I would not recommend Boston ivy for wood or vinyl siding since it can creep underneath or behind the siding and is difficult to remove without damaging painted surfaces. Cutting the stems of any vines and waiting for them to wilt and die before removing them can minimize the damage to trees and walls.
Baseball fans, want some interesting info on Wrigley Field’s Boston ivy? Check this out;
Comments or questions? Email Garden-Lou at gardenloustl@gmail.com
Words and photos by Jo Batzer
© Jo Batzer, garden-lou.com-2024, All rights reserved.
