Sunflowers are one of the most iconic summer flowers, and with a quick snip of dead or dying blooms, you can keep them looking fresh all season. Sunflowers make a cheerful addition to any garden with their bright yellow petals and tall stalks, and learning how to maximize the number of blooms you get is worth it!
Deadheading sunflowers will yield more blooms if you grow branching sunflowers, which naturally produce multiple flower heads. There’s no need to deadhead single-stem sunflowers as they will only have one central stalk and flower before they are done blooming.
While deadheading is a straightforward task, there are a few tips to keep in mind to ensure you’re doing it correctly and leaving behind the best part of your sunflower plant.
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Why you should deadhead sunflowers
Deadheading sunflowers is a simple yet effective task that any flower gardener should do. Removing the spent blooms will ultimately help you enjoy more flowers for longer. No sense in letting your sunflower put energy into making seeds when you’d rather enjoy more blooms, right?
- Get more flowers
- Extend the blooming season
- Keep the garden tidy
- Make room for new, stronger growth
- Prevent self-seeding
How to deadhead
All you need to trim your sunflower plant is a clean pair of garden pruners or shears. Branching sunflower stems don’t grow as thick as the central stem of single-stem sunflowers, so it won’t take a lot of muscle to cut.
Using your garden shears or pruners, cut the stem just below the spent bloom, being careful not to damage the developing flower buds below. You can leave a few inches of the stem behind or cut back to the first set of leave nodes.
In a couple of weeks, you should start to see new blooms forming where you made your cuts. And if you keep up with deadheading, you can enjoy sunflowers in your garden over a month or more, rather than just a week or two.
When to Deadhead Sunflowers
If your gardening goal is to get as many sunflowers as possible, then the time to deadhead is once the flowerhead has started to wilt. The petals will begin to droop and fall off, and the center of the flower may start to dry out. The flowerhead may even tip over, a sure sign that it’s past its prime and ready to be cut.
If you leave a sunflower to fade entirely on the plant, you’re letting the plant think its job is finished and that it’s time to produce seeds. By snipping off the flowerhead before it has a chance to fade fully, you’re encouraging the plant to keep producing new blooms.
On the other hand, if you want to have a mix of fresh blooms and one or two flower heads to save seeds for next year, you can leave a flower or two on the plant. This might still slow down flower production, but not as much as leaving every dead flower behind.
To harvest seeds, leave the sunflower head on the plant long enough that it gets pollinated and starts to form seeds in the center of the flower. The flowerhead will tip over to face down, and you’ll see the rounded end of the sunflower seeds packed into the center.
Once all the petals have dropped off, and the flowerhead starts to yellow and feel dry, you can finally cut it.
Store the seed head somewhere dry to finish curing. Some people like to put the seed head in a paper bag and hang it in their garage so that the bag catches any seeds that drop.
Is pinching the same as deadheading?
Pinching and deadheading are different, but both encourage plants to produce more flowers. Pinching is done early on when the plant is still growing and developing its flower buds, whereas deadheading is done after an open bloom starts to fade.
Not all sunflower cultivars need to be pinched, though.
A branching sunflower will naturally grow multiple stems, so there’s no need to pinch them when young. Flower growers don’t usually pinch single-stem sunflowers since they are grown for one long, central stem to cut for bouquets.
However, if you want to try for multiple flowers, you can pinch them back when they have 4-6 leaves. This will prompt the plant to produce 2-4 smaller sunflowers instead of one larger one.
I only recently learned that this would work on single stem sunflowers when I came across this American Society For Horticultural Science study. I’ll be trying it on my ProCut Gold sunflowers this summer!
Sometimes nature helps pinch your sunflowers for you. Slugs, rabbits, and deer can all come by for a snack, eating the tops and leaves of your sunflower plants. If that happens and you have the space, leave the plant for a few weeks to see if it starts to grow back and form new leaves and branches.
If it does, there is no need to pinch the plant further. Doing so will only slow the plant down more, and you might not get sufficient growth before the end of the season to get any beautiful flowers.
If you’re not sure that you still have time to plant more sunflowers, read this post next to find out: How Late Can You Plant Sunflowers? Check Your Zone & Date Here.
Once your sunflowers are completely done for the season, it can still contribute to the garden. Jump to this article for some ideas: 7 Ways To Repurpose Dead Sunflowers (Seeds, Stalks, and More)