What happens if you don’t pinch dahlias?

Dahlias are beautiful summer-blooming tubers that produce gorgeous flowers in a wide range of colors, shapes, and sizes. They are a favorite for gardeners looking to add vibrant colors to their landscape. One of the key techniques used to maximize the growth and flowering of dahlias is called “pinching.” This refers to the practice of using your fingers to snip off the top few inches of the stems. Pinching helps promote bushier, stockier growth and more profuse flowering. But what happens if you neglect this simple practice? Here’s an overview of how dahlias grow and what occurs when pinching is omitted.

The Purpose of Pinching Dahlias

Let’s first understand why pinching dahlias is recommended. Dahlias form their flowers on the tips of the stems. If left unpinched, they tend to grow with tall, spindly stems that produce just a flower or two. Pinching them forces the plants to develop multiple side shoots off the main stem. More side shoots equal more growth tips to form flower buds. The end result is a shorter, bushier, and more floriferous plant.

The ideal time to pinch dahlias is when they are around 12-18 inches tall. Use clean pruners or fingernails to remove 3-4 inches from the top growth. This stimulates branching from just below where you pinched. Doing this prompts the plant to grow sideways instead of just upward. It delays flowering slightly, but you end up with a much nicer looking plant by mid to late summer.

What Happens if You Don’t Pinch?

If you opt to not pinch your dahlias, here is what you can expect:

  • Tall, leggy growth – Without pinching, dahlias grow rapidly upward. This results in long, skinny stems that look floppy and unattractive.
  • Fewer blooms – With all the energy directed into vertical growth, you’ll get only a flower or two at the top of each stem. Less branching means less flowers overall.
  • Weak stem strength – The fast vertical shoots often lack the thickness and stem strength needed to support the heavy dahlia blooms. Expect flopping.
  • Smaller blooms – The flowers that do form on unpinched plants tend to be smaller and less vibrant.
  • Reduced longevity – Weakly branching plants peter out faster. Their flowering window is shorter than well-pinched plants.

As you can see, omitting pinching typically results in tall, sparse plants with small blooms. Your dahlias will be leggy, floppy, and short-lived compared to properly pinched plants. While pinching does slightly delay flowering, it pays off later in the season with abundant large blooms until frost.

Exceptions to Pinching

While pinching benefits most dahlias, there are a few exceptions:

  • Miniature varieties – The smallest dahlias, under 12 inches tall, often don’t require pinching. Check specific variety requirements.
  • Green-leafed single dahlias – The open-centered simple blooms on single dahlias rarely need pinching.
  • First year tubers – Young tubers in their first year of growth sometimes skip pinching. Let them establish good roots and growth.

Outside of these cases, plan on pinching your dahlias for best results. Timing wise, pinching around mid-summer is ideal in most climates. Watch for those stems to hit 12-18 inches and pinch 3-4 inches off the top growth.

How to Pinch Dahlias

Pinching dahlias is quite simple. Wait until they reach 12-18 inches tall, then follow these steps:

  1. Use clean, sterilized pruners or pinch with your fingernails.
  2. Remove the top 3-4 inches of each stem by pinching directly above a set of leaves.
  3. Make your cut at an angle to prevent water from pooling on the stem.
  4. Disinfect pruners between plants to prevent disease spread.
  5. Drop the pinched stem tops onto soil to decompose and feed the roots.
  6. Repeat process on every stem and branch.

Within about 2 weeks, you should see vigorous new shoots forming where you pinched each stem. This stimulates robust branching that will soon become covered in flowers. Depending on the variety, you may do a second pinch later in summer on particularly tall stems if needed.

Results of Proper Pinching

What can you expect from properly pinched dahlias?

  • Bushy, compact, robust plants.
  • Strong stems that support the blooms well.
  • Abundant flowering starting midsummer and lasting until frost.
  • Up to dinner plate-sized blooms on large varieties.
  • Enhanced flower color and form.
  • Long vase life – pinched stems last over a week cut.
  • Continual reblooming through fall – pinched plants flower until killed by frost.

In every desirable way, a pinched dahlia plant outperforms an unpinched one. Make pinching part of your seasonal care routine to maximize your enjoyment of these beautiful flowers. Train yourself to pinch on time every year for stunning end results.

Troubleshooting Pinching Problems

If you are pinching properly but still seeing less than ideal growth, look at these troubleshooting tips:

Problem Cause Solution
Minimal branching after pinch Pinching too early or late Time it when plants are 12-18 inches tall
Leggy growth resumes Not pinching low enough on stem Remove 3-4 inches of stem tips when pinching
Flowers still small Insufficient light Give plants at least 6 hours of direct sunlight

Troubleshooting your pinching technique and growing conditions can help optimize your results. Dahlias require sun, space, and timely pinching for their best performance.

Conclusion

Pinching dahlias at the right time encourages bushy, compact plants blanketed in colorful blooms. Omitting pinching results in tall, sparse plants with small flowers. Take the few minutes needed to pinch your dahlias when they reach 12-18 inches tall. Removing 3-4 inches from the stem tips prompts prolific side branching and abundant flowering. With dahlias, proper pinching makes all the difference between an average display and a spectacular showing of these summer garden stars. Make pinching an annual ritual for dahlia success.

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