Sorry, haven't grown any of those. Would love to see picts when they bloom!

By pinching, are you referring to stopping the plant by pinching off the top green growth to force the lateral branches to develop, or disbudding where you take out the side buds to improve the size/quality of the main bud?

Forcing the laterals. I am inconsistent with disbudding as well.

Neither are necessary for the casual gardener, so no worries! It's good practice, but not essential.

Both are very important if you are planning to enter blooms into a dahlia show, or need to have a flush of marketable blooms to sell. The disbudding of the wing buds not only encourages the plant to grow the center bud to it's full potential, but also gives the grower a longer stem for vases. Stopping the plant encourages more branches so multiple flowers bloom at the same time, instead of just the top bloom.

I have gotten very lazy with both, but try hard to 'get with it' in a special row reserved for show plants.

I should clarify... when you stop a plant, you delay the first bloom by a couple of weeks. It can make the wait seem like FOREVER, when checking your plants for blooms every day. (What's that saying? 'A watched pot never boils?')

The plant is naturally 'stopped' growing upwards when the 'terminal' bud appears. That's when many varieties decide to start growing the laterals. However, many other varieties don't bother waiting for that top terminal bud, and branch out much earlier... these plants would not benefit from stopping (pinching out the top growth).

Hope this explains better.

It does. Mine seem to have very eager laterals this year. The bottom ones are almost as tall as the plants themselves. It may be August before I see buds/blooms on these plants.

Here's a tidbit of trivia that blew my mind when I was taught it... Each variety has a genetically-dictated time to bloom, based on the number of leafsets the plant has (between 6 and 20 leafsets). In other words, some varieties have the terminal bud after six leafsets from the tuber (like Blackberry Ripple and many other small bloomed varieties), while other varieties have their terminal bud after 17 or 20 leaf sets. Often, these are the larger bloom varieties, but not always. This knowledge of individual varieties can be utilized to time the blooming.

I was taught this by Martin K., who is a master showman in Canada. He timed the leafsets for the dahlia shows, starting with stopping the plant, to ensure that the plant's first flush coorisponded with the shows he was entering. He has spreadsheets showing the leafset count of his favorite show varieties, along with the optimum schedule to perform tasks for a specific goal.

This amazed me when I learned this, and did quite a bit of counting until proving the truth of it to myself. Too detailed for me, though. I don't bother counting now.

Wow! I was wondering if there was something like that behind the science of growing dahlias. I don't know how I got the number 6 in my head, but I was trying to stop the terminal right around 6 leaf sets. When I went to do it I would see a little bud sitting there.

I am the same way. Any bloom I get makes me giddy.