Pruning Sunflowers

Pruning is an essential part of plant care for annual and perennial sunflowers. Trimming the plant can maintain a balanced and even look, rejuvenate new growth, and encourage more flowers. Before cutting your sunflower plant, it’s essential to know what type of plant you have and understand what you want to achieve by pruning. Properly pruning sunflowers helps the plants thrive and adds bright, bold blooms to your space.


When to Prune Sunflower

Perennial sunflowers are herbaceous, and new growth appears in the spring. Trim the new growth back by half in mid to late spring. Prune the plant again in mid to late summer. Annual sunflowers can also be cut back in late spring. Trim the stems back so the plant is about half the size it was to start. Do not prune annual sunflowers once the plant has set buds.

Deadhead perennial sunflowers to tidy up the plant and encourage more flowers. Remove the flowers when they start to fade. Annual sunflower plants die when the flowers fade, so it's unnecessary to deadhead the plant.

Why Prune Sunflower

Pruning sunflowers promotes a dense, bushy appearance, making the plant more full. More branches also mean more flowers, so trimming the plant will set you up for more abundant blooms. Deadheading perennial sunflowers forces the plant to redirect energy into new growth, which means more flowers. Perennial sunflowers can become leggy, so a second trim around mid-summer resets the plant and creates a tidy appearance. 


How to Prune Sunflower

Step 1 - Cut sunflower plants back by half in mid to late spring.

Annual and perennial sunflowers should be cut back in early spring to promote branching, creating a full plant. Do not prune annual sunflowers after buds appear.

Step 2 - Cut back perennial sunflowers a second time around mid-summer.

Perennial sunflowers can become straggly as the growing season wears on, and a second trim rejuvenates the plant and promotes more growth.

Step 3 - Pinch back spent flowers from perennial sunflowers.

Deadheading perennial sunflowers extends the bloom cycle and encourages the plant to produce more flowers.

Sunflower Pruning Tips

  • Prune perennial and annual sunflowers by half in early to mid-spring 
  • Do not prune annual sunflowers once the plant has flower buds
  • Cut back perennial sunflowers again by mid-summer if the plant is leggy or overgrown
  • Prune spent flowers on perennial sunflowers to encourage more blooms
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Author Alison Cotsonas - Published 05-01-2023