Germination temperature
About 18-24 °C (65-75 °F).
Flower growing guide
Plains coreopsis, also called calliopsis or goldenwave, is a fast annual wildflower with yellow petals marked maroon at the centre. Its seed germinates readily without any pre-treatment, as long as it is left uncovered in the light.
About 18-24 °C (65-75 °F).
On the surface; press in, do not cover.
About 7-14 days.
Light helps germination: leave the seed uncovered.
None needed.
Direct sowing is easiest; young seedlings can also be raised in trays.
The seed is small and dark. Mixing it with a little dry sand makes it easier to scatter thinly over a bed or meadow patch.
Not needed. Coreopsis seed germinates readily without treatment (Lady Bird Johnson Wildflower Center).
Not needed. Plains coreopsis has no cold requirement; in its native range it is simply sown in late autumn or spring.
Not needed. Soaking makes such small seed sticky and hard to spread evenly.
A University of Alaska Fairbanks seed-starting chart gives 18-24 °C (65-75 °F) for calliopsis. Mild, settled weather suits it better than extreme heat.
Sow on the surface of fine, firm soil or seed compost and press the seed in with your palm or a board. Do not bury it.
Light, sandy, well-drained soil. Plains coreopsis tolerates poor soil but not waterlogged ground (NC State Extension), so avoid heavy, rich mixes.
Keep the surface just moist with a fine spray until seedlings appear. Uncovered seed dries out quickly, so check it daily in sunny weather.
Light improves germination (Lady Bird Johnson Wildflower Center), and the Alaska chart lists it as light-requiring. This is the most common reason for failure: seed raked in deeply often stays dormant.
About 7-14 days in the 18-24 °C range.
Seedlings grow quickly. If you started them in trays, plant them out while they are still small, before the roots fill the cell, and water them in well.
In beds, thin direct-sown seedlings so each plant has room: mature plants grow about 30-45 cm (1-1.5 ft) wide. In a meadow mix they can be left closer.
Keep young plants watered until they are established, then water only in long dry spells. Plants reach about 60-120 cm (2-4 ft) in garden conditions, and often less in poor soil.
Cause: seed buried too deep or allowed to dry out. Fix: resow on the surface, press it in, and mist it daily until germination.
Cause: damping-off in cold, wet, overcrowded trays. Fix: sow thinly in clean compost, avoid overwatering, and give seedlings good light and air.
Cause: southern blight, a soil fungus listed for this plant by NC State Extension, favoured by heat and wet soil. Fix: remove affected plants with the surrounding soil and do not replant coreopsis in that spot.
Cause: rich soil, heavy feeding or shade. Fix: grow in full sun in lean soil, sow closer so plants support each other, or give tall plants light twiggy support.
Plains coreopsis is a temperate annual. In the Indian plains it does best sown in the cooler, drier months after the monsoon for flowers in late winter and spring; in the hills sow in spring. Very wet weather and soggy soil cause rot.
Give plants at least 6 hours of direct sun a day. Lean soil keeps them compact and full of flowers.
Removing faded flowers encourages new blooms and limits heavy self-seeding (NC State Extension).
Seed ripens about four weeks after flowers fade; collect it when the inner bracts start to darken, clean off the chaff and store it dry and cool (Lady Bird Johnson Wildflower Center).
The flowers feed many bees, butterflies and other pollinators, which makes coreopsis a useful annual for wildlife beds.
Sow plains coreopsis on the surface for a quick, easy carpet of golden, maroon-eyed flowers.
No. Light helps the seed germinate, so sow it on the surface and press it in. Keep it moist with a fine spray until it sprouts in about 7-14 days.
Coreopsis tinctoria is an annual. It flowers in its first season and often comes back from self-sown seed if some flowers are left to ripen.
Yes. Calliopsis, goldenwave and plains coreopsis are common names for Coreopsis tinctoria, which was formerly called Calliopsis bicolor.
Usually because the soil is too rich, the plants are fed too much, or they get too little sun. Grow them in lean, well-drained soil in full sun.