Grow and Care for False Sunflower

Grow false sunflower in full sun and ordinary soil that drains. Tags may also say oxeye sunflower. It is not a Helianthus sunflower.

Give it full sun and average soil that drains

False sunflower is a prairie clump. Give it sun and it holds 3 to 6 feet of orange-yellow daisies through summer. [1] [2] Shade makes floppy stems that need a stake. Rich, wet ground does the same.

Pair it with other full-sun prairie plants

Partners should want the same sun and average soil: ornamental grasses, coneflower, black-eyed Susan, blazing star, and other late-summer daisies. Leave a path so you can deadhead without trampling neighbours.

Plant after frost, with the crown at soil level

Plant nursery starts after frost in spring, or in early fall with enough weeks for roots to take. Set the crown at the same depth it grew in the pot. [3]

1. Pick full sun and ground that drains after rain.
2. Dig a hole as deep as the pot and a little wider. Do not bury the crown in a compost collar.
3. Set the plant at pot depth, backfill with the soil you dug, and water to settle.
4. Space clumps about 18 to 24 inches apart. Tall species needs room to 3 to 6 feet high.
5. Water through the first weeks, then taper to ordinary moisture.
6. Expect seedlings nearby. Pull extras if you want a fixed edge.

Grow compact kinds in a pot

A pot works for shorter cultivars if it is at least about 12 inches across, with drainage holes, and a mix that dries between waterings. Empty the saucer after rain. Full sun still applies. Ground is easier than a small bowl that stays wet.

Divide every few years to renew the clump

Clumps often fade after a few seasons. Division in fall or early spring keeps a stand going.

1. Dig the clump when the soil is workable and not waterlogged.
2. Split it into pieces that each have shoots and roots. Discard a dead woody center.
3. Replant at the same depth, water in, and keep evenly moist until new growth takes.

Deadhead, and cut back in late May for shorter stems

Spent blooms left on the plant end the show early. A late May cut keeps tall kinds from flopping.

1. In late May, if you want a shorter finished plant, cut stems back by about one-third to one-half. Bloom may start a couple of weeks later.
2. Through summer, snip spent heads down to a leaf pair so new buds keep coming.
3. After the last bloom, either cut the stems to a few inches or leave the seed heads for birds through winter.
4. In spring, clear the dead top before new growth starts. Skip the May height cut on already-short cultivars.

Straight species, Asahi, or Burning Hearts

Culture is the same. Height and leaf color are the choice. Do not treat a shop list of twenty names as a different plant.

H. helianthoides is the straight prairie plant — 3 to 6 feet, sandpapery opposite leaves, gold daisies with a cone disk. ‘Asahi’ is a double golden selection, often around 30 inches, for denser flower heads. ‘Burning Hearts’ brings purple stems, dark foliage, and gold rays with a reddish disk on a 3 to 4 foot clump.

Not a true sunflower — and not oxeye daisy

True sunflowers are Helianthus. False sunflower usually keeps its rays on the head as it fades, and holds the flower more upright. Many Helianthus heads nod, and the rays drop. The bracts under a Heliopsis head sit in two or three short rows, not a stack of long tapered ones. [4]

Oxeye daisy is a different white daisy. A tag that says bleeding heart false sunflower is a dark-leaf Heliopsis cultivar, not Dicentra bleeding heart.

Set it in full sun, plant after frost, deadhead through summer, cut back in late May if you want shorter stems, and read the tag so you did not buy a Helianthus sunflower.