How to Top Dahlias
Why top?
Topping (also called “pinching”) encourages dahlias to branch out, creating a fuller, sturdier plant with more flowering stems. It’s especially useful for cut flower gardens or compact, lush border plantings.
Benefits of Topping
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Encourages bushier growth
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Leads to more flowering stems
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Promotes stronger, more wind-resistant plants
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Ideal for cut flower production
Step-by-Step Guide
Step 1: Wait for the Right Height
Allow your dahlia plant to grow to 12"–16" tall (typically 4–6 sets of true leaves).
Why wait?
The plant needs enough foliage and strength to recover and push out new side shoots after topping.
Step 2: Locate a Leaf Node
Look down the stem to find a healthy leaf node (where a pair of leaves or small side shoots are emerging).
You’ll be cutting just above this point.
Tip: Choose a node about 3–4 sets down from the top.
Step 3: Make the Cut
Using clean pruners or snips, cut off the top 3–4 inches of the main central stem just above a leaf node.
CAUTION: If you top when the plant is young, you avoid having a hollow stem which can fill up with water and rot the plant. If you find that the top of the plant is hollow after you top it, it will take a week or so for the tube to seal. Then it is safe to water the dahlia from the top again.
Step 4: Watch the Magic Happen
Within a week or two, the plant will respond by pushing out two or more new shoots from that node, creating a bushier shape and more future bloom stems.
As the plant grows:
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Remove any tiny shoots low on the base of the plant to prevent crowding.
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Lightly prune extra inward-growing shoots if it becomes too dense.
