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Cosmos

Cosmos spp. bipinnatus, sulphureus

Category: Flowers

Cosmos are tall, graceful plants in cutting, natural, and cottage gardens. Lovely, saucer shape flowers can be single or double, with fluted petals or cupped centers. Colors are white, a range of pinks, cranberry, and sunset/yellows. Continued dead-heading or picking will keep plants blooming all summer. Cosmos need no special soil and like it on the hot, dry side. If you have a spot in your garden where other flowers don't thrive, try cosmos! Fertilizing is not recommended, as fertile soil leads to lush foliage with few or no flowers. Bright Lights is a fiery yellow/orange that looks stunning in the late summer/fall garden. A shorter variety, it is harder to use in the vase. Cosmos is a self-seeder. Stems are prone to breaking- staking is highly recommended, either individually or a double layer of nylon netting- one at 12-18" (30-45 cm) from ground, the second 12-18" (30-45 cm) above.

How to Grow Cosmos

Quick Info

Spacing
1/Square
Depth
Water
1 in/week
Season
Warm
Frost
Semi-Tolerant
Height
2-4 ft
Germination
7-10 days
Germination Temp
65-75 °F
Sprout to Harvest
75-90 days
Soil pH

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Pests

Diseases

Beneficial Critters

Growing from Seed

Cover seeds lightly.

Planting Considerations

Cosmos need no special soil and like it on the hot, dry side. If you have a spot in your garden where other flowers don't thrive, try cosmos! Fertilizing is not recommended, as fertile soil leads to lush foliage with few or no flowers.

Harvesting

Deep picks of the stems provide tall, airy stems perfect for cottage/natural arrangements. Pick as soon as color is showing in bud (cracking). If the center of the flower shows pollination, flower will not last in vase. Stems before budding are a lovely greenery in bouquets.

Pruning

Pinching seedlings encourages branching (pinch after 4-5 sets of true leaves have emerged).

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