Grow and Care for Dahlberg Daisy

Grow Dahlberg daisy in full sun and sandy soil that drains. Dahlberg daisy is Thymophylla tenuiloba, also called bristleleaf pricklyleaf — a small Texas annual, not a shooting star and not a garden marigold.

Give it full sun, sandy soil that drains, and little extra water

Dahlberg daisy is a low mound of threadlike, aromatic leaves with half-inch yellow daisy heads. Sit it in full sun so the stems stay short and the flowers keep coming, in soil that dries after rain. [1] Sandy or rocky ground is the usual fit. Average garden soil works if water still runs through; wet clay around the roots is the main reason plants rot. [2] Water a new planting until it is settled, then let the top of the soil dry before you water again. Established plants take dry weeks. A humid, wet summer in a heavy bed is a poor match, even if the label promised drought tolerance. [3] It is a dry-sun plant, not a bog annual. If the leaves yellow and the crown softens, the soil stayed wet, not dry.

Plant after frost, at the same depth as the pot

Set nursery plants out after the last frost, in a sunny, draining bed you will not need to move later. Set the crown at the same depth it grew in the pot, firm the backfill, and water it in the same day. Space plants about 8 to 12 inches apart so the mounds can fill without sitting in one another's wet foliage. [4] Keep the soil just moist while it settles, then ease off. Do not plant it before frost, and do not bury the crown.

1. Wait until after the last frost, in a full-sun bed that drains.
2. Plant at the same depth the crown already grew in the nursery pot.
3. Space plants about 8 to 12 inches apart, then firm the soil so there are no air pockets around the roots.
4. Water thoroughly the same day, then let the soil dry between waterings once the plant is settled.

Deadhead, or shear it once if bloom slows

Dahlberg daisy opens small yellow heads from summer into fall. If you want more flowers, pinch or snip the spent heads before they set seed. If bloom slows in midsummer heat, shear the mound lightly — about a third of the height — and it will push new stems for a later flush. Leave the last heads if you want volunteers next year. To raise plants from collected seed, see Growing Dahlberg Daisy From Seed.

The leaves smell lemony when you crush them. Pull the plants after frost in a cold garden; they do not overwinter as a woody shrub. In a mild winter the crown may persist, and seedlings often return on their own in gravel and dry edges.

• Deadhead spent flowers if you want a longer flush and fewer seedlings.
• Shear the mound once if bloom slows in the heat, then let it refill.
• Leave the last heads if you want volunteers, and pull extras where they are not wanted.

Not a shooting star — and not a garden marigold

Some tags call this plant shooting star. Garden shooting star is Dodecatheon, a spring woodland plant with reflexed petals, not a small yellow daisy in dry sun — see How to Grow Shooting Star. Garden marigolds are Tagetes. They are bigger bedding plants with denser flower heads, not this threadleaf Texas annual — see How to Grow Marigolds.

Bidens is another threadleaf yellow daisy sold for baskets. It wants more regular water and often trails harder than this mound — see How to Grow Bidens. Greenthread is Thelesperma, a taller prairie daisy with even finer stems, not this 6-to-12-inch edging plant — see How to Grow Greenthread. Garden coreopsis is a different daisy, often a larger clump — see How to Grow Coreopsis. Damianita is Chrysactinia, a woody evergreen mound from the same dry country — see How to Grow Damianita if that is the shop tag.

If the mound collapses by midsummer, the soil stayed wet or the air was humid. Move the next plants into full sun with sand that drains, and let an established clump dry between waterings.