How to Grow Celosia—a Showstopping Annual That Blooms All Summer Long

Celosia plants are anything but usual or subtle. A group of plants in the Amaranth family, celosia are easy-to-maintain summer annuals known for their upright feathery flower heads that come in vibrant neon colors. They can be planted en masse along a border, interspersed throughout your garden for a pop of color, or displayed in pots. Celosia thrives in warm climates, making it a great addition to the summer landscape. It needs plenty of sunlight, well-draining soil, and adequate water to stay healthy. To ensure this plant thrives in your landscape, we spoke to experts who explain what you need to know about caring for celosia.

Types of Celosia Plants

Celosia is a diverse group of plants, but there are three types that are commonly grown as ornamentals. While they look quite similar, there are a few key differences between each, says Nancy Trautz-Awot, horticulture specialist at Burpee Gardening. 

Celosia Plumosa

Celosia plumosa, or plumed celosia, is known for its compact, upright feathery blooms that have a sort of flame-like appearance. This is the most popular variety, says Nicole Shah, gardening expert and co-founder of Garden Girls.

Celosia Cristata

Commonly known as cockscomb, this specific type has compressed and unusually shaped feathery blooms, says Trautz-Awot says. It has the appearance of tropical coral. The blooms often grow to be so large and heavy that they need to be staked.

Celosia Spicata

This variety has a singular flower stalk that looks similar to wheat, which is why it's nicknamed the wheat celosia. Wheat cultivars often have the most limited color palette compared to plumed and cockscomb.

How to Plant Celosia

Celosia plants are typically grown as annuals but can be planted as tender perennials in zones 10 to 11. They are easily found at most plant stores and garden centers throughout summer. Before purchasing, turn the container over to make sure the roots are not growing out of the bottom. Root-bound celosia can have a hard time adjusting after being transplanted.

1. Dig a hole about twice as wide as the root ball and the same depth.
2. Remove the plant from its container and place it in the hole, spacing each plant about 6 to 18 inches apart, depending on variety.
3. Backfill with soil and water well.
   

Starting Celosia Seeds Indoors

You can also start celosia seeds indoors to get a head start on the growing season. "Sow seeds indoors 6 to 8 weeks before the last spring frost or directly outdoors after the frost," says Carrie Spoonemore, co-creator of Park Seed's From Seed to Spoon app. "Celosia seeds are tiny, so handle them carefully."

1. Fill small pots or seed starting trays with seed starting mix.
2. Sow each seed 1/4 inch deep, as they need light to germinate.
3. Water well, letting the soil dry slightly before watering again.
4. Cover the pots or trays with a plastic cover.
5. Keep the seeds in a warm area with indirect sunlight (or use grow lights).
6. Once the seeds germinate (7 to 10 days), remove the cover.

How to Care for Celosia

Celosias are summer annuals that need sunlight and warm soil temperatures to thrive.

Light

Celosia performs best in areas where it will receive six to eight hours of full sun per day.

Soil 

When planting celosia, use a well-draining soil with plenty of nutrients. Trautz-Awots suggests choosing a soil with a lot of organic matter, such as compost, mixed in. 

Water 

This plant prefers moist soil, but do not overwater your celosia as it doesn't like wet feet. "Water when the top inch of soil is dry, typically every few days," says Spoonemore.

Fertilizer 

Use a balanced fertilizer, such as a 10-10-10, every 4 to 6 weeks during the plant's growing season, says Spoonemore.

Pruning

As celosia's blooms fade throughout the growing season, cut them off using clean scissors or pruners. Called deadheading, this maintenance chore helps encourage more blooms. "Deadheading can be done by pinching off the flowers just above the first set of leaves," says Celosia.

How to Propagate Celosia

Propagating celosia from cuttings is a simple process. Snip about 5 or 6 inches off the top of a tall, mature celosia plant, gently remove the leaves from the bottom half, and then place the stem in a cup filled with water. The water level should hit just above where the leaves were removed. Wait for roots to develop—you'll be able to see this more easily if you place the cuttings in a clear jar—and then transplant into soil.

Growing Celosia in Containers

When growing celosia in containers, always use pots with drainage holes to prevent water from building up at the bottom, which can lead to root rot, says Spoonemore. Also ensure the container you're using is large enough. "Start with a pot at least 6 to 8 inches in diameter for young celosia plants, and consider the mature size of the variety you choose," says Spoonemore. "A larger pot will accommodate root growth and prevent the plant from becoming root-bound.

Pot the plant in a container with high-quality potting mix that is well-aerated and rich in organic matter. You'll know it's time to repot celosia when the roots grow out of the drainage holes or the plant's growth appears stunted. "Choose a pot that is one size larger, refresh the potting mix, and gently loosen any tightly bound roots," says Spoonemore.

Common Problems With Celosia Plants

Celosias are celebrated not just for their vibrant foliage but for their low-maintenance care. As is the case with other plants, however, be on the lookout for signs of distress or disease so you can help nurse your plants back to health when problems arise.

Mildew and Root Rot 

Overwatering celosia plants can result in mildew, leaf spot, or root rot. "Prevent these issues by ensuring proper drainage and air circulation. Water at the base of the plant rather than from above to keep foliage dry," says Spoonemore. "If diseases occur, remove affected leaves and treat the plant with a fungicide for powdery mildew or improve drainage and adjust watering practices for root rot."

Sun Scorching 

While celosia prefers warm and sunny spots, too much of a good thing can stunt their growth or result in browning of the leaves or flowers. If you notice this, move the plant to a shadier spot. Very young transplants may be more susceptible to sun scorching, so keep a closer eye on them.

Mites and Aphids 

Aphids and spider mites are two pests that may infest celosia. "Prevent them by keeping the plants well-watered and avoid overcrowding," says Spoonemore. "Treat infestations with insecticidal soap or neem oil. Reapply as necessary and monitor for new pests."