Last Updated on October 20, 2022 by Plant Mom Care
Celosia, a small of short-lived perennials or summer annuals from several tropical regions, are plants with distinctive showy flowers. Their beautiful flowers can add color to your garden, on your balcony, and indoors and they are frequently used in floral arrangements.
In landscapes and gardens of flowering plants like pansies, marigolds, and petunias, celosias particularly the cockscomb variety can add a stunning display of colors when grown together in garden beds.
These ornamental plants are called cockscomb, feathery amaranth, fire red, or king coral, for the texture and colors of their flowers. Indoor gardeners and plant collectors love growing this species because of their unique and beautiful flowers.
Mature plant heights vary between 6 – 36 inches in height. In addition, these plants are very easy to maintain, making them perfect for novices.
Celosia Light Requirements
These plants thrive under full sun and need 8 hours of sun to grow well. Always select garden locations that get the maximum exposure to daylight to grow these plants. They can tolerate partial shade but produce better blooms under full sun.
These plants are drought-tolerant and can survive dry soil conditions. Conversely, they are sensitive to overwatering because very moist conditions attract root rot fungus. They need moist but well-draining soil to produce healthy flowers. Allow the topsoil to become dry before watering.
Depending on growing conditions, water them 3 or 4 times weekly, particularly in summer, to prevent the soil from becoming completely dry. Reduce watering in autumn and winter.
These plants prefer high humidity levels of around 90% during summer, although average indoor humidity levels of around 40% are perfect for attractive blooms.
The ideal temperature is between 60 – 80 °F for these plants. They can grow outdoors as summer perennials or annuals in hardiness zones 10 – 11.
The best soil for these plants is rich and loamy, well-draining. Mix equal parts of perlite (for drainage), peat moss (retains moisture), and organic compost (to increase nutrient levels). This improvement helps the plant produce more colorful flowers.
Since these plants are annuals (living for only 12 months), they don’t need repotting.
These plants can be propagated from cuttings. Use sterilized shears and cut 4 to 6 inches from the top of the stems. Remove leaves from the lower portion of the cuttings. Place the cuttings in water to cover the lower portion where the leaves were removed. Once roots develop, transplant the cuttings directly into the soil.
Plants can be propagated by seeds in indoor containers. Sow the seeds in a planting tray of fresh potting soil and cover them with ¼ inch of fine sand or vermiculite. Keep the soil slightly moistened and wrap the container with plastic film to retain high humidity.
Maintain temperatures at 75 – 80 °F to help the seeds germinate within 7 – 10 days. After germination, remove the plastic, transplant the seedlings to larger individual containers or in your garden, and water regularly. Make sure the topsoil is dry in between watering. Feed the seedlings every month to boost growth.
Fertilize the soil with a 3-1-2 (NPK) fertilizer once a week or add organic compost. Nitrogen-rich fertilizer provides nutrients to boost foliage growth, while phosphorus boosts bigger flowers.
Once the plant has established itself and is growing healthy, switch the fertilizer to one with a higher ratio of phosphorus for bushier growth and more flower production.
During the spring and summer, the flowers and stems need regular deadheading and pinching to encourage bushier growth and new flowers. Deadheading spent flowers helps promote more flower production and prevents self-seeding. Place the flowers in a container indoors, let the flowers dry and collect the tiny black seeds to grow for many more years.
Also, tie the large flower plumes of taller varieties to a stake to support them and prevent them from falling.
Celosia Common Problems
These plants can suffer from pest infestation and fungal disease when they’re overwatered with poor drainage and insufficient light. These pests and diseases are easy to cope with if they are detected early.
Pests like aphids, spider mites, and nematodes can be very destructive. Spider mites are troublesome because they damage the foliage, particularly by discoloring, drying, and making leaves brittle. The mites thrive in warm, humid conditions like these plants enjoy.
Aphid damage includes removing nutrients by sucking sap and a major infestation can make the plants wither and die. If not treated, aphid excrement can provide sooty molds with a medium to infect the plants.
Spray the plant with neem oil or insecticidal soap when tiny spots or soft-bodied insects appear on the foliage and repeat the treatment after two weeks.
Nematodes attack the roots, inhibit root growth and prevent plants from becoming mature. Plant marigolds as a cover crop around the plants.
Brown leaf spots can appear when fungus spores land on wet foliage in cool and humid conditions. These spots can appear as tan, dark brown, or black subjects on the stage of infection. Remove infected leaves and stems to prevent the spores from spreading. Provide good air circulation and water the plants regularly to keep them healthy and prevent these diseases.
Stem rot fungus spores are dormant in the soil until wet and cool weather and warm, humid conditions are suitable for spore germination and start the infection. The fungus infects the stems and creates dark brown lesions that merge and can cover all the stems of the plants as the infection progresses.
This causes wilting of stems and foliage above the infected area.
Stem rot can be prevented by maintaining good air circulation, good drainage, and increased exposure to sunlight. Water the plants moderately and use a recommended fungicide drench on the soil.
Over-watering can also bring problems such as root rot. The water-logged soil blocks nutrient and oxygen absorption and salt build-up. Such conditions create yellow leaves and wilting of stems and roots. The plant must only be watered when a few inches of topsoil become dry to prevent root rot.
Does celosia come back each year?
Since they are annuals, these plants do not reappear each year unless you harvest and sow seeds indoors before the first six weeks of spring. If they grow outdoors, they might come back every spring due to self-seeding if the plants are not deadheaded.
How long do celosia plants live?
The lifespan of these plants is only 12 months. The plants start in spring and start flowering within 3 months.
Is celosia an indoor or outdoor plant?
They make good indoor potted plants if protected from hot or cold drafts. They can also thrive in gardens or pots outdoors.
Can I grow celosia in pots?
These plants can grow well in pots indoors or outdoors provided they have well-draining soil and sufficient light.
How do you keep celosia flowering?
Give them lots of sunlight, warmth, good soil, and careful watering and they’ll reward you with plenty of flowers. Deadheading spent flowers also encourages the plants to produce more flowers.