Blooming Cosmos Flowers: A Quirky Summer Blossom Growing Guide
Unleash Your Garden's Realm of Color with Cosmos: An Unbiased Guide!
Cosmos, the sun-kissed, vibrant flowers, are a gardener's delight! Bursting with cheerful blooms, they offer a spectrum of dazzling shades ranging from pure white to deep purple, captivating everyone with their irresistible charm. These beauties are a perfect fit for a lush English cottage garden or a finely curated landscape. What's more? They're the ultimate pollinator's paradise, flowering lavishly from midsummer until the first frost in fall.
Don't forget, cosmos possess a long growing season, extending your garden's colorful allure from summer to autumn. They grow tall and full, adding statuesque vertical depth to your landscape, while their thick foliage effectively keeps weeds at bay. Let's dive into some insider tips on growing and caring for these dynamic delights from our gardening gurus!
Julia Keel, a master of specialty cut flowers from Full Keel Farm, and Jennifer Joray, the regenerative flower mistress of Eastern River Farm, share their wisdom to help you enjoy the cosmos' beautiful blooms all season long.
Growing Cosmos: The Timing Game
Determining the ideal planting time for cosmos depends on your local climate. Plant cosmos once the threat of frost has waned and soil and air temperatures are consistently warm, says flower farmer Julia Keel. "In north Florida, this is around mid-March, but in colder regions, this will be much later," she explains, cautioning that cold temperatures might hamper your cosmos' growth. To lock in the precise planting window, consult the USDA gardening zones map for details on the last frost in your area.
Step-by-Step Cosmos Planting
You can start cosmos seeds indoors five to seven weeks before your region's last spring frost, or directly in the ground. Here are the simple steps to plant cosmos:
- Sprinkle seeds over the soil.
- Lightly rake the seeds so they are about 1/16 to 1/8 inch deep.
- Cover the seeds with a light layer of soil and vermiculite.
- Press the seeds gently into the soil to ensure good contact.
- Keep the soil moist but not soggy.
- Thin the seedlings out to have them 12 to 24 inches apart once they germinate.
If easy cosmos is more your style, cut down the previous season's plants and lay them flat across the soil where you'd like them to regrow the next year. "Mother Nature takes care of the rest, gifting you with cosmos the following season," advises Jennifer Joray.
Diverse Spectrum of Cosmos
Some gardeners prefer a rainbow of cosmos, creating a stunning mix of colors, heights, and styles. "It's essential to carefully read the descriptions of the cultivars you're planning to grow to ensure the plant height is appropriate for your intended use," suggests Keel. Explore your garden center and seed catalogs to find cultivars that meet your preferences, such as:
- Cosmos sulphereus: These flowers generally have a yellow hue, native to meadows and grasslands. They grow between 4 to 7 feet tall.
- Cosmos bipinnatus: A vibrant mix of purple, pink, and white blooms, the flowers of C. bipinnatus range from 1 to 6 feet in height.
- Cosmos atrosanguineus: Also known as chocolate cosmos, this species boasts purple-brown flowers with a rich fragrance.
Discover the perfect cosmos companion for your garden!
We'll Handle the Care, You Handle the Enjoyment!
Cosmos are low-maintenance yet rewarding blooms. Here are some tips to nurture your cosmos:
- Light: Cosmos love full sun and should be planted in an area with at least six hours of sunlight daily, preferably unobstructed by buildings, trees, or fences.
- Soil: Cosmos are adaptable to many soil types, but thrive best in well-draining soil. Sandy soil needs to be amended with compost for optimum growth.
- Water: Keep the soil consistently moist but not soggy, and cosmos will be content. They are somewhat drought-tolerant once established.
- Temperature: Cosmos grow best in moderate summer temperatures and germinate best when soil temperature ranges between 70 and 72 degrees Fahrenheit. They perish easily in frost, so start them indoors five to seven weeks before planting them outside once the soil temperature reaches 60 degrees Fahrenheit – similar to basil and tomatoes.
- Fertilizer: Cosmos require minimal fertilization, and oversupply of nitrogen can lead to excessive growing and limited flowering.
Keep It Trim and Tidy
Pruning cosmos during the growing season can prevent them from getting unruly. "Cosmos plants have thick stems, and we prefer thinner stems for design purposes, so we 'pinch' the plants back when they have four to five pairs of leaves or are about 12 inches tall," recommends Jennifer Joray. Cut above the top pair or two of leaves to promote numerous stems per plant. Cosmos are prolific, so you don't need to deadhead individual flowers to encourage new blooms, though doing so will yield a neater look.
Harvesting Cosmos
Cosmos add that extra pop of color and whimsy to flower arrangements. When harvesting cosmos for vases, Julia recommends cutting single varieties once they are just budded up and showing color. For double varieties, wait until the blooms are about half open.
Elevate Container Gardening with Cosmos
If your outdoor space is confined, you can easily grow cosmos in containers on your porch or balcony. Choose shorter varieties that appear proportionate and don't require staking. Opt for a pot with a drainage hole to let excess water escape. Place the container in a sun-drenched spot, checking the soil moisture regularly, as container plants dry out more quickly than ground-grown plants.
Common Hiccups
Cosmos are generally resistant to pests and diseases, but watch out for these potential pitfalls:
- Lack of Support: Although cosmos appear wild and charming without support, they can benefit from a light corralling or something to lean against.
- Insects: Aphids, spider mites, or sometimes Japanese beetles might snack on your cosmos leaves. Consult your local extension for guidance on treating these pests.
- Air Flow: Cosmos can develop powdery mildew if there is too much congestion. Ensure good airflow by thinning plants out as seedlings.
Growing Cosmos: Frequently Asked Questions
- Does cosmos return every year? No, most cosmos are annuals, but they may produce self-seeders for the following spring.
- Does cosmos spread rapidly? Yes, over time cosmos will scatter and self-seed, but they're not invasive and don't spread with runners.
- Can I scatter cosmos seeds? Yes, you can sow cosmos seeds directly on the soil. However, make sure you gently rake the seeds into the soil so they're at least 1/16 to 1/8 inch deep for successful germination.
- Martha Stewart's delightful English cottage garden might include vibrant cosmos flowers, adding a dazzling spectrum of colors to the lush landscape.
- cosmos flowers are a perfect addition to a finely curated home-and-garden, providing essential nectar for pollinators during summer and autumn.
- For gardening enthusiasts who love a rainbow of colors, a mix of cosmos cultivars like Cosmos sulphereus, Cosmos bipinnatus, or Cosmos atrosanguineus adds an eclectic touch to one's home-and-garden lifestyle.
- To ensure proper growth, it's essential to determine the best planting time for cosmos based on local climate, following guidelines provided by experts like Julia Keel and Jennifer Joray.
- Keeping cosmos plants well-maintained and pruned can prevent their unruly growth, providing thinner stems ideal for flower arrangements and preserving the overall garden's aesthetic appeal.
