Dahlias Started In Trays Are Short-Jointed

This dahlia tuber hasn't grown much since planting in soil in a seed tray nearly two months ago. I believe this to be good news. Can I explain:

It's not how MUCH it has grown, but the TYPE OF GROWTH it has made, which is important. Keeping cool, in good light, and restricting water and space has produced a miniature plant - one that is far more short-jointed than traditional dahlias started early in pots, especially if heat has been applied.

So what? Why is this important? Surely we want the plant to get big as soon as possible, don't we? And what does it matter how short-jointed a plant is if it is to be buried in a hole?

Well, I think it matters quite a lot. As you can see, there are at least three nodes within the first 2.5 inches (7 cm) of shoot. And because the soil in the tray is shallower than a pot, this sets the plant lower in the ground . . . And because the nodes are so low, they will be even deeper in the ground where there should be even more moisture . . . And because each node can produce an additional set of adventitious roots, we should have some great growth potential . . . And because each node should produce two new shoots, we should get more flowers . . . And because the shoots are coming from below ground, the plant should be more compact and more stable, so should not need staking. The advantages seem almost endless. The only problem is that there's a lot of catching up to do - it's that 'tortoise and hare' thing again. Will there be enough time left in the season? Let's hope so.

See also:
Producing Drought-Resistant Dahlias In Shallow Soil
How Geotropism Can Build Drought-Resistance In Dahlias