Threadleaf coreopsis or tickseed (Coreopsis verticillata) is a fine-leaved flowering perennial that has tons of great varieties to choose from. It is a terrific plant for perennial gardens and massing. Most varieties grow 1-2 feet high and spread 1-2 feet or more. Coreopsis has a long bloom period when deadheaded and, in some ways, blooms more like an annual than a perennial. Coreopsis does best in full sun but can handle part sun. In full sun, it blooms more profusely and grows more densely. Likes moist, well-drained soils but is drought tolerant once established and does poorly in overly moist soils.
Tickseed spreads via rhizomes and self seeds so it can get a bit pushy in a perennial garden. Plan on keeping it in check as needed. Even with the extra work it offers such a great bloom period and fine textured foliage that its hard to pass up if you have part to full sun available.
Notable varieties: ‘Moonbeam’ is a lovely light yellow variety that is especially beautiful. ‘Zagreb’ which is a shorter growing variety and there is a great pink variety Coreopsis rosea (Pink Tickseed).
|Common Name:||Threadleaf coreopsis or tickseed|
|Botanical Name:||Coreopsis verticillata|
|Plant Description:||Late spring/Summer blooming perennial with fine featherry foliage that is a fast spreader and has a season long bloom period.|
|Foliage:||green fine feathery texture.|
|Flower:||Single layer of smooth petals surrounding a small yellow centers.|
|Bloom Time:||June to September|
|Soil Type:||Loamy. Moist well-drained soils are best.|
|Sun:||Full sun to part sun|
|Specific Conditions:||Deer resistant|
|Style Considerations:||Nice dense spreading habit. Massing and grouping are great options. Fine texture foliage and a long bloom period. Great for massing.|
|Watering:||Watering weeklyif needed is typically best. Can handle some drought conditions.|
|Mulching:||Not required but always helps especially if you need to add organic matter to the soil.|
|Fertilizing:||Not needed if you have healthy humus-rich soil with plenty of organic matter.|
|Weeding:||Does a great job at stifling weeds due to its dense mound like foliage that keeps most weeds from getting through.|
|Deadheading:||Deadhead individual spent flowers to prevent it from going to seed and to rebloom.|
|Dividing:||Yes, in early spring as they emerge or early fall|
|Transplanting:||Early spring when they start to appear or early fall is best but anytime works with sufficient watering.|
|Pests:||If planted in the right conditions it has few pests.|
|Winterizing:||Cut back any stems that remain 2-3 inches above the ground after the first hard frost or two (when the ground freezes). You can also use straw or pile some leaves over the plants.|