Heirloom

Sylphid

Celosia argentea plumosa

Photo: Thomas Cross · Wikimedia Commons · (Public domain)

Harvest

95-100d

Days to harvest

📅

Sun

Full sun

☀️

Zones

10–11

USDA hardiness

🗺️

Height

9-18 inches

📏

Planting Timeline

Zone:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Start Indoors

Transplant

Direct Sow

Start Indoors

Transplant

Direct Sow

Showing dates for Sylphid in USDA Zone 7

All Zone 7 flower →

Zone Map

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Sylphid · Zones 10–11

What grows well in Zone 7? →

Growing Details

Difficulty

Easy

SeasonWarm season annual

ColorLemon-lime

Zone-by-Zone Planting Calendar

Zone	Indoor Start	Transplant	Direct Sow	Harvest
Zone 1	May – June	July – August	July – September	—
Zone 2	April – May	June – July	June – August	—
Zone 11	January – January	January – February	January – March	—
Zone 12	January – January	January – February	January – March	—
Zone 13	January – January	January – February	January – March	—
Zone 3	April – May	June – July	June – August	—
Zone 4	March – April	June – June	June – July	—
Zone 5	March – April	May – June	May – July	—
Zone 6	March – April	May – June	May – July	—
Zone 7	February – March	April – May	April – June	—
Zone 8	February – March	April – May	April – June	—
Zone 9	January – February	March – April	March – May	—
Zone 10	January – January	February – March	February – April	—

Succession Planting

Sylphid hits harvest around 95–100 days, but it keeps producing plumes once you start cutting — so a single planting carries most of the season on its own. That said, if you want a steady cutting supply rather than one big flush, stagger two or three small sowings about 3 weeks apart, starting seeds indoors in late February and pushing your last direct sow no later than early June in zone 7. Anything started after mid-June won't have enough warm days to reach full bloom before fall nights drop below 50°F and shut the plant down.

Complete Growing Guide

Highly uniform plants produce lemon-lime colored plumes that complement any color combination. Feathery plumes sit on tall, straight stems. Also known as cockscomb, Prince of Wales feather, and prince feather. Unauthorized reproduction and sale of seeds is prohibited by the breeder. According to Johnny's Selected Seeds, Sylphid is 95 - 100 days to maturity, annual, open pollinated. Notable features: Use for Cut Flowers and Bouquets, Ideal for Drying and Crafts.

Light: Full sun (6 or more hours of direct sunlight a day). Soil: High Organic Matter, Loam (Silt), Sand. Soil pH: Neutral (6.0-8.0). Drainage: Good Drainage, Occasionally Dry. Height: 0 ft. 9 in. - 1 ft. 6 in.. Spread: 0 ft. 9 in. - 1 ft. 0 in.. Spacing: 12 inches-3 feet. Growth rate: Rapid. Maintenance: Low. Propagation: Seed. Regions: Coastal, Piedmont.

Harvesting

Sylphid reaches harvest at 95 - 100 days from sowing per Johnny's Selected Seeds. As an annual, harvest continues until frost ends the season.

Smooth, glossy, shiny capsule contain many seeds

Color: Black. Type: Capsule.

Edibility: The leaves and young shoots are cooked and used in soups and stews. The seeds yield edible oil.

Storage & Preservation

Sylphid plumes are best kept fresh by standing cut stems in clean water at room temperature (65-72°F) away from direct heat and ripening fruit. For immediate display, keep at 50-55°F with moderate humidity to extend vase life to 10-14 days. To preserve long-term, hang-dry bundles in a warm, well-ventilated, dark space for 2-3 weeks to maintain color. Alternatively, press individual plumes between parchment paper for floral arrangements, or preserve in silica gel for maximum color retention. Dried plumes can be stored in airtight containers for 1-2 years.

History & Origin

Sylphid is open-pollinated, meaning seed saved from healthy plants will produce true-to-type offspring. Listed in the Johnny's Selected Seeds catalog.

Origin: Tropical Africa

Advantages

+Lemon-lime plumes offer unique color that complements diverse garden palettes
+Tall straight stems eliminate need for staking or support structures
+Highly uniform plants ensure consistent results across entire planting
+Easy to grow variety ideal for beginning and experienced gardeners
+Feathery plume texture adds visual interest and movement to gardens

Considerations

-Seed saving prohibited by breeder limits future cost savings for growers
-Requires 95-100 days for maturity making succession planting challenging
-Prone to root rot in poorly drained or overly wet soil

Companion Plants

Marigolds and nasturtiums are the two worth prioritizing near Sylphid. Marigolds (Tagetes spp.) emit thiophene compounds from their roots that suppress soil nematodes, and their scent can throw off aphids that would otherwise target your celosia. Nasturtiums pull double duty as a trap crop — aphids tend to pile onto them first, buying your Sylphid some time before a colony gets established. Zinnias and cosmos are good neighbors too, mostly because they share the same full-sun, warm-season rhythm and don't compete hard for water or root space at 9–18 inches tall.

Keep Sylphid well away from black walnut (Juglans nigra) and fennel. Black walnut roots and leaf litter release juglone, a compound toxic to a wide range of annuals — in zone 7 Georgia gardens, old walnut trees along fence lines catch people off guard every season when their nearby beds just quietly fail. Fennel is allelopathic in its own right and tends to stunt whatever's growing close to it; plant it in its own corner, away from anything you're trying to cut regularly.

Plant Together

Catmint

Repels ants, mosquitoes, and rodents while attracting bees

Zinnia

Attracts butterflies and beneficial predatory insects

Chives

Natural fungicide properties and repels aphids

Marigold

Repels nematodes and aphids while attracting beneficial insects

Lavender

Deters pests with strong fragrance and attracts pollinators

Nasturtium

Acts as trap crop for aphids and cucumber beetles

Sweet Alyssum

Attracts beneficial insects like lacewings and hoverflies

Cosmos

Provides beneficial habitat for predatory insects and pollinators

Keep Apart

Black Walnut

Releases juglone toxin that inhibits growth of many flowering plants

Fennel

Allelopathic effects inhibit growth of most companion plants

Eucalyptus

Strong allelopathic compounds suppress nearby plant growth

Troubleshooting Sylphid

What you'll see, why it happens, and what to do about it.

Seedlings collapse at soil level, stem pinched and dark at the base, 7–14 days after germination

Likely Causes

Damping off (Pythium or Rhizoctonia spp.) — fungal rot triggered by overwatered, poorly drained seed trays
Sowing too densely, which traps humidity around stems

What to Do

1.Ditch the affected tray — there's no saving it once damping off starts
2.Start fresh in sterile seed-starting mix, not garden soil or old potting mix
3.Water from the bottom and run a small fan near your seedlings to keep air moving

Leaves covered in white or gray powdery coating, usually showing up mid-summer when nights cool slightly

Likely Causes

Powdery mildew (Erysiphe spp.) — common in late summer when day/night temperature swings widen
Crowded planting that reduces airflow between plants

What to Do

1.Space plants at least 12 inches apart to improve airflow
2.Remove and bag heavily affected leaves — don't compost them
3.Apply a diluted neem oil spray (2 tsp per quart of water) every 7 days until symptoms stop spreading

Stunted growth, yellowing leaves, and sticky residue on stems and foliage

Likely Causes

Aphid infestation (commonly Myzus persicae or Aphis gossypii) — they cluster on new growth and undersides of leaves
Ants farming aphids, which actively protect colonies from predators

What to Do

1.Knock aphids off with a strong stream of water — do this in the morning so foliage dries before evening
2.Encourage or release ladybugs (Coccinellidae) — a single adult eats 50 or more aphids per day
3.If the infestation is heavy, spray insecticidal soap directly on the colonies every 4–5 days

Flower plumes turning brown and mushy after prolonged wet weather, not recovering when it dries out

Likely Causes

Botrytis blight (Botrytis cinerea) — gray mold that takes hold in warm, humid conditions above 60°F
Overhead irrigation or rain that keeps the plumes wet for more than a few hours at a stretch

What to Do

1.Cut out affected plumes cleanly with sanitized shears and throw them in the trash
2.Switch to drip irrigation or water at the base of the plant — keep the flowers dry
3.Give plants more room; 12–15 inches between plants cuts the humidity that Botrytis cinerea needs to spread

Frequently Asked Questions

How long do Sylphid flowers last in a vase?▼

Sylphid cockscomb plumes typically last 10-14 days in a vase when kept in cool conditions (50-55°F) with fresh water changed every 2-3 days. At room temperature, expect 7-10 days of display. For longer-lasting arrangements, dry the plumes by hanging them upside down in a warm, dark location for 2-3 weeks—dried plumes maintain their lemon-lime color for years.

Is Sylphid good for beginners?▼

Yes, Sylphid is excellent for beginners. This heirloom variety is rated easy to grow, producing highly uniform plants with minimal fuss. It thrives in full sun and tolerates standard garden conditions well. With 95-100 days to harvest, first-time growers can expect reliable results and beautiful lemon-lime plumes with straightforward care.

Can you grow Sylphid in containers?▼

Yes, Sylphid can be grown in containers. Use well-draining potting soil in pots at least 12 inches deep to accommodate the tall, straight stems. Ensure containers receive 6+ hours of full sun daily. Container plants may need staking for support and consistent watering, especially during hot weather, to prevent stress.

When should I plant Sylphid seeds?▼

Start Sylphid seeds indoors 6-8 weeks before your last spring frost, or direct sow after the last frost date when soil has warmed. Seeds germinate best in warm conditions. Transplant seedlings outdoors once all frost danger has passed. With a 95-100 day harvest window, summer planting ensures blooms by late fall.

What does Sylphid cockscomb look like?▼

Sylphid produces distinctive lemon-lime colored, feathery plumes that sit atop tall, straight stems. The uniform plant structure and vibrant plume color make it highly ornamental. The feathery texture and elongated flower heads resemble the 'Prince of Wales feather,' which is an alternate common name for this variety.