How to Grow and Care for Cleome (Spider Flowers)

Cleome plant with pink and white flower clusters on thin stem with long stamen

The Spruce / Evgeniya Vlasova

Cleomes aren't the most popular annuals sold at home improvement stores and nurseries, and it may be because they look rather weedy as young seedlings in 6-packs. Unlike pert marigolds or dazzling New Guinea impatiens, cleomes usually do not start blooming until they are well established in the garden. Though they can be planted in early spring, many gardeners opt for a late fall sowing directly in the garden soil. They grow quickly to a height of 3 to 4 feet.

Common Name Cleomes, spider flower, Rocky Mountain bee plant, stinking clover
Botanical Name Cleome
Family Cleomaceae
Plant Type Annual
Mature Size 1.5 to 5 feet tall and 1 to 2 feet wide
Sun Exposure Full sun, part sun
Soil Type Average, well-drained 
Soil pH Acidic to neutral
Bloom Time Summer
Flower Color White, pink, lavender, rose
Hardiness Zones 10, 11
Native Area South America

Cleomes Care

Averaging 3 to 4 feet in height, cleomes provide a welcome tall focal point in the annual garden, where compact bedding plants tend to rule. The pink, purple, white, and lavender flowers do not emit a noticeable fragrance, yet hummingbirds, butterflies, and hummingbird moths are drawn to these flowers all summer long.

Cleomes easily start from seed in the garden and tend to be hearty from germination. Once started, the plant seems to take care of itself. What is more, the upright stalks need no staking as long as they are growing in full, bright sun. This plant shrugs off pests and diseases.

Cleome plant with small flower clusters of pink and white petals surrounded by long stamen closeup

The Spruce / Evgeniya Vlasova

Cleome flowers on thin spiky-looking stems with white flower clusters and pink blooms

The Spruce / Evgeniya Vlasova

Cleome plant with pink flowers clustered in garden

The Spruce / Evgeniya Vlasova

Cleome plants with small pink and white blooms in front of flower garden

The Spruce / Evgeniya Vlasova

Light

Cleome flowers grow best in full sun, as shady conditions can make them grow so tall as to topple over. If you start with transplants, you will see blossoms from early summer until the first frost. Gardeners growing cleome flowers from seed usually see their first flowers in mid to late June, depending on the climate.

Soil

Cleomes do best in average garden soil or rich well-drained garden loam.

Water

Once established, cleomes are drought-tolerant, making them a welcome addition to the xeriscape garden. Add a 3-inch layer of organic mulch to their planting bed, and you will decrease their water needs even further.

Temperature and Humidity

For successful germination, cleomes need higher-than-normal temperatures. Fluctuating day/night temperatures are essential for optimum germination. During the day, temperatures should range from 80 to 85 degrees Fahrenheit; nightly temperatures should stay between 68 and 70 degrees Fahrenheit. The humidity should be from 90 to 100 percent. As the plant grows, the temperatures can be lower, from 75 to 80 degrees Fahrenheit during the day and 60 to 65 degrees Fahrenheit at night. Cleomes are not frost-tolerant.

Fertilizer

If using good well-drained soil and mulch, no fertilizer is necessary.

Types of Cleomes

There are over 180 varieties of cleomes, but only a few are quite popular among gardeners for their color and growth habit. These are some of the most common:

  • "Helen Campbell" - this variety offers pure white flowers and needs very little care.
  • "Linde Armstrong" - a thornless variety with pink, rose, or mauve flowers that can bloom throughout the season.
  • "Rose Queen" - Fragrant and eye-catching, this cultivar comes in shades of purple, white, cherry, and rose.
  • "Sparkler Bush" - this unique hybrid plant has a bushy look with white or pink flowers.
  • "Spirit Series" - this compact plant reaches up to 48 inches with white, pink, or lavender flowers.

Pruning

Cleomes need very light pruning. Snip off dead leaves or damaged areas during the growing season. If the plants are spindly right before planting, trim them back by half to encourage new growth once they are in the ground.

Propagating Cleomes

Cleomes grow from seed, so propagating is not only unnecessary but tends to be an unfruitful endeavor.

How to Grow Cleomes From Seed


Cleome flowers are easy to start in the garden from seed. Perhaps too easy, as the plants can self-seed to the point of being a nuisance. The seeds need light to germinate, so you can just sprinkle them in the garden after the danger of frost is past and look for seedlings after 10 days. Alternatively, sow them in the autumn, and they will germinate when conditions are just right in your garden the following growing season.

If you do allow the plants to self-seed, thin the newly emerging seedlings to allow at least 18 inches between plants. This improves the vigor of individual plants, encouraging the most blossoms from each plant. If you want to limit cleome’s self-seeding habit, spend time each week plucking the long seed pods that form under the flowers throughout the season.

Potting and Repotting Cleomes

You can grow cleome in large containers, but choose a compact variety like the 'Sparkler' series for best results. Combine your potted cleomes with a mounding flower like vincas and a trailing flower like petunias for the most full and lush look. 

How to Get Cleomes to Bloom

Fortunately for the home gardener, cleomes are quite easy plants to grow and maintain. A good watering habit will help establish them in good soil; once established, they are drought-resistant and respond well to appropriate pruning. Deadheading the cleomes will help encourage new growth while preventing it from self-seeding, thus keeping the garden neater.

Common Problems With Cleomes

Cleomes are surprisingly resistant to pests and quite resilient against common plant diseases. Mildew and rust might become a problem if the plants are too crowded; thin the bed to avoid this problem. If the soil is not healthy, the plants will not be as healthy as they could be, and that will attract insects that could shorten the life of the cleomes.

FAQ
  • How long can cleomes live?

    Plan to enjoy the cleomes for a single season. When they die back in fall, plant new seeds, or wait until spring to sow seeds as soon as the ground can be worked.

  • What are alternatives to cleomes?

    The casual form of cleomes makes them well-suited to the cottage garden or naturalized meadow. Mix cleomes with zinnias, cosmos flowers, black-eyed Susans, salvia, or celosia. These plants all thrive in the same sunny conditions and moderate irrigation that cleomes love. 

  • Can cleomes grow indoors?

    It's possible to begin cleomes indoors and later transplant them to the garden. However, their tall growth habit and need for direct, full sun make it tough to grow them indoors throughout the season.