Q. What ate all of my wild violets? All that's left are the veins and the stems!
---Connie, up in Erie, PA
A. Well, this sure is a change of pace! Generally when we see 'wild violets' in a subject line, the email is more like this one:
Q. We moved into a new house two years ago, and the back lawn was more weeds than grass. Despite the two large silver maples that shade the lawn, I have most of the weeds under control, but have not been able to control the spread of violets. It seems that the only way to control them would be to kill everything and start over or dig them all up (an impossibility due to their sheer numbers). I tried mowing at a low setting to lop off the flower buds, but that goes against the normal advice of not scalping the lawn. It also didn't get rid of them!
---Rolf in Alexandria, VA
A. That's much more like the typical violet vituperation we receive! Unfortunately, Rolf is taking the all-too typical homeowner stance of "I'm going to grow a lawn there no matter how little chance I have of success!" The basic truth is that even the most shade-tolerant grass needs four hours of sun a day; and even if it does get that much, Rolf will still have to contend with the intense competition for water and nutrients from those giant maple roots. Growing grass under trees is a tough job.
And his 'low-mow brainstorm' may have actually been more like lawn-a-cide. Grasses in shady areas need to be cut even higher than we typically recommend—at three and a half inches—to have enough surface area to try and collect the minimum amount of sunlight they need to survive. Scalping—especially right before the season of summer heat stress arrives—will probably just turn the area into a dust bowl or a mud puddle, depending on what kind of weather he gets.
But it's not surprising that wild violets are the last of the 'weeds' resisting his removal efforts. Despite their fragile look and ephemeral beauty, they are tough plants, and they are highly resistant to chemical herbicides. The only sane way to remove them would be to try one of the new non-toxic herbicides whose active ingredient is iron, or to dig up and replant the clumps somewhere they're wanted.
But even that might not give Rolf a shot at a nice lawn. His shady, 'tree-infested' conditions make him the best candidate for a woodland garden I've seen in a long time. Instead of fighting a battle with Nature that he'll never win, he should install some native plants that do well in dry shade in that area and let the violets be. Or, if he does somehow have a decent looking lawn, mow even higher—at closer to four inches—and enjoy the violets during their brief appearance early in the season. After all, they're beautiful in the Spring…
…And edible! They look great on top of salad greens. And, like their cultivated cousins, the pansies and violas, they contain large amounts of rutin—a nutrient that strengthens capillary walls and helps reverse the visible effects of varicose and spider veins over time.
But of course, that's if you get to eat them! It's way past time to return to our main topic and try and help poor Connie eat some of hers! I have to admit that I didn't have a clue, so we picked Connie's email for one of our 'posts of the day' at the You Bet Your Garden Facebook page last month. To get the responses started, I suggested that 'the usual suspects' were the culprits—herbivores like deer, groundhogs, rabbits and such.
…Despite the fact that Connie had said 'all that's left are the veins and the stems', and those big plant eaters aren't nearly so choosy—everything would be eaten. An insect perhaps? But what kind of an insect? I've encouraged the growth of wild violets all over our property, and I never saw flowers that were 'stripped' the way she described.
Luckily for Connie, our Legion of Facebook Friends stepped in. The first comment was from someone named Mary Martin (loved you in Peter Pan!), who was squarely on Rolf's side. She posted: "I know people who would welcome anything that eats violets!"
But then Colleen Beatty of Delaware chimed in with the observation that "a number of caterpillars require violets as food. Keep an eye out for the butterflies they become; and if they are the 'culprit', maybe you should plant more violets next year."
Well, Coleen was A-Plus, Gold Star right! I did a little searching and found a great article on violets as host plants at the website of the American Violet Society. Originally published as an article in the Summer 2000 issue of The Violet Gazette, it explains that violets function as food for the caterpillars that go on to become Fritillaries; large, colorful butterflies that look a lot like monarchs to the untrained eye.
Elizabeth Scott, the author of the article, explains that towards the end of summer, the adult butterflies lay their eggs in areas where they somehow know that violets will appear the next Spring. The eggs hatch, tiny little caterpillars emerge, spend the winter under leaf litter, and then start to nibble away when the violets begin to flower—feeding from below, so people rarely see them.
But you can't miss the big butterflies they turn into! And even though I never noticed any violence to our violets, we do have a lot of Fritillaries flitting around the garden right now. Looks like we have yet another reason to love our wild violets!