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Open-pollinated seeds Asteraceae

ornamental flower

Le potager ornemental de Catherine

Red sulphur cosmos

Name: Red sulphur cosmos
Brand: Le potager ornemental de Catherine
SKU: POC-SEMENCES
Price: 4.19 CAD
Availability: OutOfStock

Cosmos sulphureus

Grow Red sulphur cosmos from these flower seeds to bring out the characteristic colour, shape and growth habit of its flowers. This sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft) in height. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. Watch the buds open and check the condition of the flowers. When the variety is suitable for bouquets, cut a few stems with a clean tool and place them in water promptly. In a flower bed, remove only the faded flowers when you want a tidy display rather than saved seeds. Direct sow in the garden after the last frost or start indoors 4 to 6 weeks earlier. Sow the seeds at a depth of 6 mm (0.2 in). The recommended location is full sun.

Sold as ±70 seeds

4 ¹⁹$

Common nameRed sulphur cosmos

FamilyAsteraceae

GenusCosmos

Speciessulphureus

TypeOpen-pollinated seeds

Botanical nameCosmos sulphureus

Reproducible seedsYes

Red sulphur cosmos belongs to Cosmos sulphureus. The plant completes its life cycle in one season. The flowers are red or dark orange. The plant reaches 1.40 m (4.6 ft) in height. Does not need staking. Long flowering period from July until frost. The flowers are abundant and much appreciated by pollinators. The shoots, young leaves and flowers are edible. These characteristics help you choose its position in the garden and compare this selection with other cultivars in the same group. Plan its location around its growth, leaving enough room to observe and care for the plant.

Full sun, well-drained, poor soil (do not fertilize with nitrogen-rich fertilizers). Direct sow after the last frost or start indoors 4 to 6 weeks earlier. Sow the seeds at a depth of 6 mm (0.2 in). Leave 40 cm (15.7 in) between plants. In Quebec, adjust the timing of planting to the frost risks in your particular area and to the life cycle of the plant. Keep the growing mix slightly moist during emergence without saturating it, and provide light as soon as seedlings appear. If sowing begins indoors, acclimatize the seedlings to wind and sun before planting them in the garden.

Position the plants where their flowers will remain clearly visible, taking their expected height and spread into account when arranging the planting. Leave access for watering at the base, following buds as they open and removing damaged stems. Group plants with similar requirements for light exposure and soil moisture, while avoiding crowding young plants together simply to create an immediate visual effect. Leave enough room for the foliage as it continues to grow and develop through the season. For this annual, follow flowering through the season and choose which stems to keep for their seeds. Keep labels in place to recognize each variety, even after the flowers have faded. Keep these flower seeds dry until the next sowing.

In the garden

Exposure: Full sun
Life cycle: Annual

Sowing guide

Sowing & germination

Sowing depth

6 mm (0.2 in)

Spacing / density

40 cm (15.7 in)

Sowing period

Direct sow in the garden after the last frost or indoors 4 to 6 weeks before.

Propagation

Seed sowing

Growing method

These seed-starting tips for Red sulphur cosmos concern gardening in Quebec and can be adjusted to local frost risks. Direct sow in the garden after the last frost or start indoors 4 to 6 weeks earlier. Sow the seeds at a depth of 6 mm (0.2 in). Leave 40 cm (15.7 in) between plants. This crop is identified as Cosmos sulphureus. Arrange flowers according to their actual height: taller plants should remain visible without completely hiding a lower border. Leave access for cutting a stem or removing a faded flower. Observe a colour mix plant by plant; it does not guarantee every colour in each small group. Prepare the final growing site and seed-starting supplies first. For seed starting in pots, moisten the growing mix before filling the cells, then sow without compressing it into a hard mass. For direct sowing, remove large soil clods and mark a row that you can locate again after watering. Distribute seeds according to the intended spacing rather than pouring several into one spot. Water the growing medium gently so that the flow of water does not displace the seeds you have sown. Once the seedlings have emerged, keep the healthy young plants and allow enough space for them to continue developing. If seedlings are started indoors, gradually acclimatize them to outdoor conditions before planting them out. Handle the root ball carefully without pulling on the stem. Transplant into prepared soil, then water to help the soil settle into contact with the root ball. Flowering extends from July until frost and attracts pollinators.

Soil and care

Soil & care

Care level

Moderate

Watering

For Red sulphur cosmos, adjust watering to the stage of growth. Avoid automatic daily watering after establishment: where specified, the source describes dry soil or low-water cultivation. Water the seedbed gently so that the seeds remain in place. After establishment, check moisture near the roots rather than judging only by the appearance of the leaves. Direct water to the base and adjust the amount according to rainfall. Check a wind-exposed container more often; excess water must be able to drain freely.

Soil type

When growing Red sulphur cosmos, the source recommends poor, well-drained soil (do not fertilize with nitrogen-rich fertilizers). Prepare soil that the roots can explore, without large clods around the seeds. Assess drainage after rain as well: water should not remain around the crown for long. In containers, use a growing mix rather than heavy, compacted garden soil. The fertility requirements described for this plant should guide additions, without automatically adding large amounts of compost.

Fertilization

When feeding Red sulphur cosmos, begin with the fertility of the growing medium. The source recommends poor or moderately fertile soil: do not add high-nitrogen fertilizer to make the foliage artificially denser. Before applying fertilizer, examine the soil or growing mix already in use. Measure each application according to the label and the crop's needs, without combining several products at once. In containers, account for nutrients already present in the growing mix. A plant that is suffering from a lack of water cannot be helped simply by applying additional fertilizer.

Moisture

Even moisture without saturation

Seasonal care

When caring for Red sulphur cosmos, take the following characteristic into account: this sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft.) tall. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. Monitor the flower buds throughout the growing season and use a clean tool to remove any stems that have broken. Cutting flowers to make a bouquet and keeping flowers for seed saving are two different choices for managing the plants. Retain a few seed capsules only if you want seeds, watching for them to open before dispersal. Start the season with a prepared site and labelled seedlings. During emergence, check that moisture reaches the seed zone without creating a persistent puddle. After planting, observe establishment before adding more fertilizer or pruning. Remove small weeds and check damaged leaves so that isolated damage is not mistaken for a need for fertilizer. Throughout summer, adjust watering to the condition of the soil and the rain received. Check support ties after windy weather, and do not let a tie constrict a thickening stem. Make cuts with a clean tool; do not remove a healthy stem simply to improve the view. In fall, separate what should be harvested, left in place or removed according to the plant's life cycle. After detaching the stems, put the supports away and clean your tools; take care not to move diseased plant debris into other growing areas. Whether the plant returns in spring depends on its stated life cycle, not simply on the word garden in its description. Watch the buds open and check the condition of the flowers. When the variety is suitable for bouquets, cut a few stems with a clean tool and place them in water promptly.

Bloom and dimensions

Size, flowering & harvest

Mature height

1.40 m (4.6 ft)

Bloom period

Observe flowering in Red sulphur cosmos using these guidelines. This sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft) in height. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. Watch the buds and flowers according to this plant's life cycle. A stated time frame shifts with growing conditions; it does not set the same date for all of Quebec. Cut flowers for bouquets only when this use is documented.

Harvest

When growing Red sulphur cosmos, harvest only the confirmed edible parts: shoots, young leaves and flowers. Harvest healthy parts from identified plants, without mixing a similar-looking flower with this crop. Prepare the harvest using clean equipment; the rest of the plant is not automatically an ingredient.

Garden associations

Companion plants & uses

Companion plants

When choosing companions for Red sulphur cosmos, consider light, access and space. Place this plant alongside crops with compatible light and moisture needs, preserving the space required for its foliage. Plan companion planting around the available space and growing requirements. Leave enough light and air around the plant, and keep taller neighbours from covering its foliage. A practical arrangement of plants makes watering and harvesting easier to manage; it does not, by itself, guarantee protection against insect pests or an increase in yield. Keep every crop accessible and maintain its individual spacing.

Garden use

For Red sulphur cosmos, the aim is to highlight the colour, form and habit of the flowers. This sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft) in height. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. Choose the use according to the part harvested and the documented harvest stage. Keep the plants in your garden clearly identified all the way through to the time of harvesting or flowering. The seeds in the packet are for starting this crop: keep the variety label beside the plants.

Frequently asked questions

How do you sow Red sulphur cosmos seeds?

For Red sulphur cosmos, sow directly in the garden after the last frost or indoors 4 to 6 weeks beforehand. Sow the seeds at a depth of 6 mm (0.2 in). Leave 40 cm (15.7 in) between plants. To choose a sowing date in Quebec, begin with your local frost risk, then apply the timing recommended for this crop. Always plan indoor seed starting by counting backwards from the expected planting date; do not start the seeds too early simply on principle. Prepare containers before sowing and label the variety. Maintain moisture suited to the seeds without leaving standing water. When sowing directly in the garden, prepare the row before distributing the seeds and water gently.

How much space should you allow for Red sulphur cosmos?

When growing Red sulphur cosmos, this sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft.) tall. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. Arrange flowers according to their actual height: taller plants should remain visible without completely hiding a lower border. Leave access for cutting a stem or removing a faded flower. Observe a colour mix plant by plant; it does not guarantee every colour in each small group. Choose the position according to this plant's habit and growth, then leave access for watering and cutting. If the plants require a support, put it in place before their stems begin to grow longer. The distance between plants does not replace a working aisle.

How should you manage watering for Red sulphur cosmos?

For Red sulphur cosmos, avoid automatic daily watering after establishment: where specified, the source describes dry soil or low-water cultivation. Check the growing mix or soil near the roots before watering. Water must reach the root ball, and excess water must then be able to drain from the container or soil. Recent rain, wind and heat affect how often watering is needed. Water at the base rather than routinely wetting the flowers and foliage. When a plant wilts, check its root ball as well: adding water to an already saturated root ball will not solve every problem. Use a gentle stream when watering newly sown seeds. Monitor the flower buds throughout the growing season and use a clean tool to remove any stems that have broken. Cutting flowers to make a bouquet and keeping flowers for seed saving are two different choices for managing the plants.

How should you monitor the development of Red sulphur cosmos?

The growth of Red sulphur cosmos follows this profile. This sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft) in height. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. Monitor the flower buds throughout the growing season and use a clean tool to remove any stems that have broken. Cutting flowers to make a bouquet and keeping flowers for seed saving are two different choices for managing the plants. Retain a few seed capsules only if you want seeds, watching for them to open before dispersal. Watch the buds open and check the condition of the flowers. When the variety is suitable for bouquets, cut a few stems with a clean tool and place them in water promptly. In a flower bed, remove only the faded flowers when you want a tidy display rather than saved seeds.

What growth stage should you look for in Red sulphur cosmos?

For Red sulphur cosmos, watch the buds open and check the condition of the flowers. When the variety is suitable for bouquets, cut a few stems with a clean tool and place them in water promptly. In a flower bed, remove only the faded flowers when you want a tidy display rather than saved seeds. This sulphur cosmos bears red or dark orange flowers on stems about 1.4 m (4.6 ft) in height. Flowering extends from July until frost and attracts pollinators. The supplier confirms the use of the shoots, young leaves and flowers as food. The schedule is a guide, but observing the plant determines the right moment. Follow the recommended stage for the part harvested, and distinguish botanical maturity from culinary quality. Harvest with a clean tool when the stem resists, and immediately sort out damaged parts. For a bouquet flower, choose a healthy stem when this use is confirmed.

Wildlife and pets

Wildlife & precautions

Supporting wildlife

The supplier describes the flowers of Red sulphur cosmos as attractive to pollinating insects. Keep some flowers accessible while open if you want to observe these visits. The presence of insects also depends on the surrounding environment and the time of year; this information does not guarantee a particular number of visiting insects or protection against every garden pest.