Starting New Dahlias – Which Way is Best for You?

After a particularly disappointing dahlia growing season in 2024, I’ve decided to reevaluate my approach for 2025. Gardening often requires making decisions far in advance, based on what you anticipate caring about months—or even a year—down the line. As a dahlia enthusiast, this can be especially challenging if you’re the type who waits until April, right before planting season, to finalize your plans.

When you’re interested in hybridizing dahlias, the process becomes even more complex. Most gardeners rely on ordering tubers for their plants, which has its pros and cons. On the positive side, tubers guarantee you know exactly what you’re getting because they are essentially cloned copies of one variety. On the downside, they can quickly become expensive, especially if you want multiple varieties—and that’s before factoring in shipping costs.

Another consideration is the risk of dahlia diseases, like viruses. While it’s impossible to pinpoint exactly what percentage of dahlias carry viruses, the odds aren’t zero—especially with popular varieties that have been cloned extensively, sometimes thousands of times over the years. This doesn’t deter me from buying dahlias, but it’s something I keep in mind. I would say it's quite possible any dahlia grower with at least a couple varieties probably has an infected plant, if not multiple. You just might not be aware of it because the symptoms may not show until the plant is under great stress.

Buying tubers locally can help reduce costs, but it often limits your selection, and the chances of encountering diseased tubers may increase. When I say "buying local," I primarily mean at the big box stores. If you happen to be lucky enough to have a local dahlia farm, then your odds are much higher you'll get less expensive tubers that are less likely to be carrying a disease. It’s a balancing act between cost, variety, and plant health.

Opting for cuttings comes with its own set of challenges, primarily the difficulty of securing the specific varieties you want and the additional costs associated with them. Popular varieties are often in high demand, so you may find yourself competing with others to snag them. That said, I believe the chances of encountering viruses or diseased plants are lower with cuttings due to the increased rigor in testing these varieties in recent years—a significant improvement compared to two years ago. If someone at a dahlia farm is creating their cuttings without sterilizing their tools, one infected tuber can ruin everything that knife touches.

One downside to cuttings, however, is the potential difficulty in producing tubers from them at the end of the season. It can be hit and miss. While some growers report no issues, my personal experience has been less reliable. Because of this, I’m hesitant to order cuttings again unless it’s for a variety I can’t source any other way—and only if it’s something I absolutely must have. Fortunately, my “must-have” list is shorter this year, so this isn’t a major concern for me.

Growing dahlias from seeds offers some clear advantages, especially if you’re not too concerned about specific traits like double blooms or particular colors. If you simply enjoy having a variety of flowers around, this can be an excellent option. I suspect many gardeners stick to tubers simply because they’ve never considered that dahlias can be grown from seeds, much like zinnias.

The biggest benefit of growing from seeds is the cost. A single packet of dahlia seeds can yield enough plants to fill a good-sized space. Even if you’re looking for something somewhat specific, you can often find seed packets in the $10–$20 range, including shipping. Compare that to the cost of 30 plants grown from tubers—it’s a significant saving. And don’t even think about calculating the cost of 30 cuttings; that’s a level of stress no gardener needs.

Growing dahlias from seeds comes with some significant drawbacks, particularly if you’re aiming for specific traits. Unlike tubers and cuttings, which are clones of established varieties and reliably produce the plants you expect (barring a mix-up by the seller), each dahlia grown from seed is entirely unique. You won’t know the flower’s color, whether it will be a double bloom, how many petals it will have, how the bloom sits on the stem, or even the plant’s height until it matures. But if you buy a packet of dwarf collarette dahlias, you're likely to get some short stature collarettes or collarette-ish blooms. And if you buy a packet of dinner plate dahlia seeds, you're unlikely to get any collarettes. The plants will also probably be 4 - 5 feet tall.

The reality is that about 80-100% of the flowers grown from seed will likely be disappointing, unless your primary goal is simply to support pollinators. Or you're more of a general flower lover. Of the remaining 0-20% good ones in air quotes, many will still be underwhelming, and only around 1% might turn out to be spectacular. Even then, some of those standout plants might not form good tubers, others may fail to survive, and a few could bloom completely differently in subsequent years. Your gorgeous collarette might turn into a disappointing single on year two. These uncertainties make growing dahlias from seeds a challenging and often unpredictable endeavor. However, once you start getting plants you like, you can then populate your garden with those varieties quickly. And even begin crossing between those good varieties to make even more good ones.

For 2025, my plan is to focus on a few very specific tubers while also taking a chance with a couple packets of certain types of specialty seeds. If you’re considering the seed route, it’s worth spending some time researching the varieties you love and reviewing the results from companies selling those seeds. With a little digging, you can find seeds for some unique dahlia types—whether it’s an unusual pattern, color, or bloom style. I particularly enjoy reading reviews and looking at photos from other growers. While these reviews aren’t as common as I’d like, they can be either encouraging or discouraging, depending on the results shared.

If you decide to grow from seeds, be prepared for some gaps in your garden as you remove the “duds.” Don’t feel obligated to keep watering and caring for flowers that don’t bring you joy—some blooms can be surprisingly unattractive. You’ll likely end up with many basic blooms in overly common colors like red and yellow, floppy stems, simple single dahlias, or flowers that all look alike. The key is to focus on finding a few standout plants to carry forward into the next season. Over time, you can build a collection of exceptional dahlias while continually weeding out the underperformers as you go along.

The Aley Acres seed shop on Etsy.

Dahlias, Notes from a Gardener book on Amazon.

Floral Art and Landscape Painting Etsy shop.

TikTok, some gardening posts.