As we start planning our gardens and going over catalogs to choose seeds and tubers, many of us will undoubtedly purchase dahlia tubers. Some may have started checking the health of their tubers in storage. If you have been here before, you know I am a crazy dahlia lady. I just LOVE them. But these flowers can be pretty finicky and have many problems. And sometimes you have to deal with a problem by ripping it off like a band-aid. It hurts but it is necessary. This is how I feel about dealing with a dahlia issue.
Last year I could somehow tell that I would have issues with my dahlias, even as I was planting them— don’t ask me how… I just had that gut feeling— and I was not wrong. They started growing good but then one of them started showing a leave “behavior” that just did not give me a warm and fuzzy feeling. It happened over a few days when I did not check the plants. But when I did, it was obvious that something was not okay with the new leaf growth. The edges were curling and the veins of the leave looked almost embossed and the dead giveaway-- the veins looked yellow. Then it started spreading to the more mature leaves. I hoped that it was not viral but a look at the American Dahlia and Minnesota Dahlia Societies confirmed what I thought—it was viral. And based on the symptoms, it looks like it was the dahlia mosaic virus (DMV).
Some of the symptoms include yellow or green spots on leaves, wrinkling/curling of new leaf growth, and in many cases the plant is stunted or produces deformed or very few flowers.
In a situation like this there is just one course of action—remove the plant. If you do not, you run the risk it will infect other plants and you do not want that. There is no cure for a viral disease like this once the plant is infected. Viruses are infectious pathogens that, due of their small size (invisible to the naked eye), cannot be detected until you see the symptoms which is at that point, too late. The majority of the viruses are transmitted from plant to plant via a vector, or living organism, and the majority cannot survive outside its host. Of the hosts, aphids and whiteflies are considered to be the vectors that infect plants the most.
For dahlias it is a double-threat. Dahlias are particularly susceptible to viruses because tubers are propagated vegetatively, when a tuber is divided. What this means is that the plant is the result of asexual reproduction where only one plant is involved and the offspring is the result of one parent.
So, yes—it is too bad that you have to go through such draconian methods when a virus infects your plant, but it is necessary. At the end of the day I ended up losing three different dahlias, and will have to keep an eye on the rest, as sometimes an infected plant may see asymptomatic for a while.
A word of advice: after you remove the infected plant and throw it in trash (do not compost), and make sure you do not touch any other plants until you disinfect your clothing and your tools. You do not want to infect your healthy plants after you went through such trouble to eliminate the threat of the infected plant. If you love your garden this is a painful but necessary step to ensure the health of the garden as a whole.
You may find me joining some of these fun link-ups: In a Vase on Monday, Mosaic Monday, Friday Bliss, Home and Garden Thursday, Pink Saturday, Nature Notes, Dishing It & Digging It, Thankful Thursday, Grace at Home, Weekend Blog Hop, Garden Blogger's Bloom Day (15th of the Month), End of Month View (31st of the Month), #MyGloriousGardens, Six on Saturday.