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Herbs, Flowers & Specialty CropsSunflower (Cut Flower) Planting Calendar
Cut-flower sunflowers are fast and generous, but one sowing blooms all at once. A plan built on repeat sowings keeps the vases full and avoids a feast followed by a famine.
Key points
- Sow sunflowers directly after all danger of frost has passed.
- Stagger plantings by interval or by variety maturity for steady bloom.
- Space by type, from six inches for short types to two feet for giants.
- Cut when flowers are just opening and use clean water.
When should you plant sunflowers for cutting?
University of Minnesota Extension advises direct seeding after the last frost, once all danger of frost has passed. Seed germinates in about seven to ten days under good conditions, and indoor-started seedlings can go out once they have true leaves.
Use your own average last frost from the National Weather Service or your county extension office. Sunflowers do not need a head start in most areas, since direct sowing is quick.
A soil thermometer helps. Seed sown into cold, wet ground can rot or emerge unevenly, so wait for warm soil if the weather has turned cold after your last frost.
How do you stagger sunflower plantings?
The Minnesota source describes three ways to spread bloom: use varieties with different maturity times, sow the same variety every one to two weeks, or sow mixed varieties every three to four weeks. Each approach has trade-offs, and which one you use depends on how predictable you want bloom dates.
For example, if you want sunflowers over most of a warm season, you might sow a short row every week or two until the date when your area's frost typically arrives, subtracting the days to maturity shown on the seed packet plus a margin. Adjust for your own frost dates.
- Read days to maturity on the seed packet for each variety.
- Count back from your average first fall frost for the last sowing.
- Keep a log of sowing and cutting dates to improve next season.
- Leave a few weeks of cushion for slow, cool weather.
- Single-stem types give one flower and are finished.
- Branching types give several smaller flowers over time.
- Stagger plantings by one to two weeks for steady bloom.
- Mix maturity times to avoid a single glut.
How deep and how far apart should you sow?
The Minnesota guide suggests sowing seed about an inch deep. Spacing depends on the type: shorter varieties need about six inches, taller types at least a foot, and giants about two feet. Branching types need eighteen to twenty-four inches.
Cut-flower growers often plant single-stem types closer together to get uniform stems, while branching types are given more room. Follow your seed packet and adjust based on stem length and head size.
What soil and site do cut sunflowers need?
Full sun and well-drained soil produce the strongest stems. Sunflowers are deep rooted, so loosen the bed before sowing. A soil test and local recommendations guide any fertilizer, since nutrient management rules vary by state.
Wind can topple tall types, so choose a sheltered site or provide support. Keep the bed evenly watered during establishment, especially in dry weather.
Add a layer of mulch after seedlings emerge to keep weeds down and hold moisture, keeping it back from stems.
When should you cut sunflowers?
Cut when the flower is just opening, in the cool of the morning, and put stems straight into water. Single-stem varieties produce one flower per plant, so the plant is finished after cutting, while branching types can be cut repeatedly.
Strip lower leaves and keep stems out of hot sun until you finish. Clean buckets and fresh water extend vase life.
Pollen-bearing types drop pollen on tabletops, and some growers choose pollenless types for that reason. Check seed descriptions to see which kind you are buying.
What problems affect sunflowers?
Birds and squirrels may take seed, and insects and diseases can affect leaves and stems. Spacing, crop rotation and clean-up reduce problems. Ask your extension office to identify issues before treating.
If you consider a pesticide, the label is the law, pre-harvest intervals apply and applicator licensing varies by state. Sunflowers draw many bees, so protect pollinators.
What does a cut sunflower calendar look like?
Mark your average last frost, a first sowing after it, repeat sowings at a steady interval, and a final sowing date counted back from your first fall frost. Add a note for how many rows each sowing should be.
Update the plan each year based on what ran short and what was left uncut. Over time you will find the interval that fits your sales or your vases.
Plan how many stems each sowing should yield and how many you can sell or use each week, then size your succession accordingly.
Timing at a glance
| Item | Window | Caveat |
|---|---|---|
| Sunflower direct seeding, University of Minnesota Extension | After the last frost, once all danger of frost has passed; stagger every one to two weeks for the same variety | Source guidance for Minnesota; use your own frost dates and days to maturity. |
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.