How to Pinch Dahlias for More Blooms (Even If You're Nervous to Cut Them!)

If you're like me, you want as many flowers as possible from your dahlia plants.

One of the very best ways to make that happen is to pinch your plant.

I know, it feels completely backwards. You've spent weeks babying your dahlias, and now someone is telling you to snip off the top.

I promise there's a good reason.

Pinching is one of the easiest ways to dramatically increase the number of flowers your dahlia produces all season long. Once you understand what's happening inside the plant, it makes perfect sense.

Let's talk about why pinching works, when to do it, and the three different ways I pinch my own dahlias.

The Science Behind Pinching Dahlias

Here's what's happening behind the scenes.

When you remove the central growing tip, the plant redirects its energy into multiple side shoots, called lateral stems, instead of continuing to grow one main stem.

Each of those new stems is capable of producing flowers.

Then, every time you cut a flower to bring inside or deadhead a spent bloom, you're encouraging the plant to branch again.

Those new branches produce even more flowers.

Remember learning about exponential growth in school? That's essentially what your dahlia is doing all summer long.

What Happens If You Don't Pinch?

The good news is that pinching isn't required.

Your dahlias will still grow and bloom if you never pinch them.

Left alone, a dahlia naturally grows upward on one main stem until it produces a flower bud at the very top. Once that bloom finishes, the plant begins branching lower down and produces more stems.

Pinching simply speeds up that natural process. Instead of waiting for that first bloom to finish, you're telling the plant to start branching much earlier.

The result is that rather than getting one early flower, you'll usually get several flowers just a week or two later, followed by many more over the course of the season.

When Should You Pinch Dahlias?

I usually pinch my dahlias sometime in June or early July, depending on how quickly they're growing.

As a general guideline, I wait until the plant has about six sets of leaves and is 6-12 inches tall.

That isn't a hard-and-fast rule, though. If I'm pinching an entire bed and one plant only has four sets of leaves, I'll usually pinch it anyway. I'd rather pinch it a little early than have to come back later for one lonely plant.

Don't worry about making it perfect.

Pinching "imperfectly" is almost always better than not pinching at all.

Where Do You Make the Cut?

Look for the main growing stem and count up about five pairs of leaves from the bottom. Then simply remove the growing tip just above that fifth set of leaves.

That's it.

The plant will quickly begin producing several new shoots from the leaf nodes below your cut.

A Note About "Dinnerplate" Dahlias

For very large-flowered varieties, generally those with blooms six inches or larger, many growers recommend pinching a little lower, around the third or fourth set of leaves.

The idea is that the plant will still produce more stems than an unpinched plant, but not quite as many as if you pinched higher.

Fewer stems generally means larger individual flowers.

Again, I don't obsess over getting this exactly right. Sometimes I pinch higher, sometimes lower, and the plants still perform beautifully.

Three Ways I Pinch My Dahlias

There isn't one "correct" way to pinch. Here are the three methods I use, depending on the size of the plant.

1. Pinch With Your Fingers

When the plants are still small, this is my favorite method.

Count up about five sets of leaves, then use your thumb and forefinger to simply snap off the tender growing tip.

It's quick, easy, and requires no tools.

2. Use Pruners or Scissors

As the plants get larger, the main stem becomes thicker, often around one-third to one-half inch wide, and it usually becomes hollow. At that point, it's much easier to use a pair of pruners or scissors to make a clean cut.

Some gardeners worry that because the stem is hollow, rainwater can collect inside or earwigs and other insects can enter through the opening. That can happen occasionally.

Personally, I take a fairly relaxed approach.

When you're growing 800 to 1,000 dahlias like I do, you learn not to worry about every little thing. It's always ideal to pinch plants while they're smaller, but sometimes life gets busy and you get to them later.

I've heard of people wrapping the cut with aluminum foil or doing other things to protect it.

I've never bothered.

Most plants do just fine!

3. The Weed Whacker Method

This is definitely the flower farmer version.

If I'm pinching an entire field, sometimes I'll simply walk down the row with a weed whacker.

Seriously.

I'm not counting leaf sets.

I'm not measuring every plant.

I simply trim the tops off at roughly six to eight inches above the ground.

Is it perfect?

No.

Does it work?

Absolutely.

If you're nervous about pinching your dahlias, picture me with my weed wacker in hand, tearing through my field and checking this task off my list!

Be brave.

Make the cut.

Your future self will be glad you did!