We jokingly call them farmer nuggets, but here on the farm those tiny, weird, and often downright ugly tubers are the backbone of the operation.
Farming has a way of humbling you. You make your plans, sharpen your tools, tuck your tubers into the earth, and then the season unfolds however it wants. Over time, you start paying attention to the little things that quietly work – and the big things that quietly don’t.
One lesson that’s stuck with me: the best dahlias often come from the smaller tubers - generally around the size of a AA battery.
Not because I set out to prove it. It was just what I had. When you’re planting thousands of dahlias, you don’t get to hand-pick your prettiest roots. You plant what you’ve got. And what I had after shipping all the ‘good’ tubers off to customers, more often than not, were smaller tubers.
And they outperformed. Again and again.
They rooted quicker. They didn’t loaf around relying on stored starch – they went looking for sustenance. They built the kind of root systems that anchor a plant through wind, drought, and the baking heat of a summer sun. The bigger tubers? Many of them sat back, slow to root, top-heavy, and vulnerable - eventually needing extra attention as they wilted, flopped and crashed their way into late summer.
During the heat dome of 2021, I saw it play out clear as day - albeit through steamed-up sunglasses as the mercury hit 120 degrees inside the tunnel, according to my field thermometer. The plants from large tubers flopped hard. Some scorched right to the ground - too much foliage, not enough foundation. Meanwhile, the ones from smaller tubers held on. Not perfect, but upright. They had roots deep enough to draw water, and just enough top growth to survive.
That was the moment it really clicked for me. I started scratching around the base of the worst-hit plants, trying to understand what went wrong. Every single one had come from a large or mid-size tuber - and nearly all of them had minimal roots. Just enough to anchor them, but not enough to support what was happening above ground.
In the cooler evenings, the plants from smaller tubers would recover from heat wilt, cooling off and regaining posture, while the larger-tuber plants stayed slumped - still stressed, still thirsty, and likely giving off the kind of chemical signals that garden-smart pests seem to tune into. That season taught me more than any book ever could.
There’s science to back it up, too. In studies on tuberous-rooted species like Dahlia variabilis, researchers observed that stored carbohydrates in large tubers can promote rapid shoot elongation, especially when conditions favor photosynthesis and top growth. But without corresponding root development, plants get thrown off balance (Journal of the American Society for Horticultural Science).
Another study examining the effects of photoperiod on dahlia development showed that shorter days encourage tuber enlargement while longer days promote fibrous root growth – reinforcing the idea that tubers shift energy use based on context (Greenhouse Product News). When a plant has a large reserve, it’s more likely to invest in top growth quickly, which can backfire in stressful or inconsistent weather.
There’s also pest pressure. Larger, juicier tubers attract more than just admiration. Slugs, snails, and voles go for the good stuff first. Plants grown from oversized tubers that surge up early seem to become the first salad bar for pests, especially in spring when insects are hungry and roots haven’t fully anchored (Gardenia.net Pest Guide).
I’ve talked to plenty of other growers who’ve noticed the same thing. They may not say it out loud in catalogs or socials, but they know: the scrappy little tubers tend to pull their weight.
And let’s be practical. Small tubers are easier to handle, easier to store, and easier to plant. They’re less likely to rot, less likely to be chewed by voles, and more likely to root where they’re planted instead of just sitting there acting like royalty.
So if you’ve ever looked at a skinny tuber and wondered if it’ll grow – don’t overthink it. If it’s firm, has an eye, and a will to live, it’ll likely do just fine.
In fact, it might just be the best one in the row.
Could the Opposite Be True?
Sure - in some cases.
Larger tubers can act like an insurance policy early in the season. They’ve got more stored energy, which can help a plant bounce back from a late frost, hailstorm, or a rough transplant. That energy reserve might even save a plant that would otherwise stall out.
And if the tuber doesn’t push top growth too aggressively before roots catch up? It can become a slow-release food source. As the outer tissue begins to soften and break down, it can feed the surrounding soil - releasing carbohydrates, moisture, and minerals right where the young roots are searching. If it’s a healthy breakdown (not rot from pathogens), it’s a bit like burying compost with the plant. It won’t replace good soil prep, but it can give the plant a boost.
But that breakdown comes with risk. When large tubers begin to decompose in the soil, they can attract problems:
- Wireworms and other soil-dwelling larvae are drawn to soft, decaying tissue.
- Slugs and snails may target the nearby eyes and shoots, especially in damp conditions.
- Small mammals like voles and mice might dig them up.
- And fungal pathogens can take hold, especially in heavy or compacted soil.
So while bigger isn’t always better, it’s not always worse either. Like most things in gardening, it depends on the context – the soil, the weather, the timing, and the plant’s own momentum. It’s a balance between stored energy and potential pest attraction, and every grower learns to read that line a little differently.
But here’s the thing: if you’re planting at the right time - after the danger of frost has passed and conditions are warming - that advantage becomes less relevant. In fact, it can work against you. Big tubers tend to push fast top growth before roots are fully established, and that’s where things can go sideways. Fast growth without solid footing makes a plant vulnerable, especially in heat, wind, or uneven moisture.
So while I won’t argue that big tubers don’t have their place, I’ve found that in real field conditions - when planted at the right time - the small ones do just fine. More than fine, actually. They thrive.