Spider Flower

Despite its unfortunate name, the Spider flower is a popular annual plant for colorful summer flower beds. We introduce the South American beauty and provide planting and care tips.

Silke Eberhard Silke Eberhard
Jul 23, 2021 03:01 pm
readtime icon 5 Minutes
Growth type
  • one year old
Growth height (from)
from 80 cm to 150 cm
Growth width (from)
from 40 cm to 70 cm
Growth characteristics
  • upright
Flower color
  • purple
  • red
  • pink
  • white
Flowering time (month)
  • July to October
Flower shape
  • Cluster
Leaf color
  • green
page format
  • 3-piece
  • 5-piece
  • 7 pieces
  • pointed
Light
  • sunny
Soil type
  • stony to sandy
Soil Moisture
  • moderately dry to fresh
Lime compatibility
  • lime-tolerant
Nutrient requirements
  • moderately nutritious
Decorative or utility value
  • Flower Decoration
Winter Hardness
  • frost-sensitive
Use
  • Flowerbeds
  • Bouquets
  • Garden fences
  • Group planting
  • Planters
  • Rose companion
Garden style
  • cottage garden
  • Flower garden
  • Prairie Garden
  • Rose Garden
  • Pot garden
Bee Friendly
bee friendly plant
Origin and Appearance

With such a name, it certainly wasn’t easy for the South American spider flower to win over flower lovers. But it succeeded: After persistently appearing at garden shows and in public parks, it became a trend plant and now adorns many a garden. The name is derived from the long-stalked carpels that remain on the plant after each individual flower fades, resembling the legs of a spider. In the plant kingdom, the spider flower and its relatives (which are less suitable for gardens) are members of the family Cleomaceae.

The spider flower is an annual that displays its flowers from July to October in loose terminal clusters. It grows to a height of 30 to 40 inches, while tall varieties reach heights of up to 60 inches. The Summer flowers grow from the ground with several shoots and do not branch out – as a result, the slightly thorny stems often look a little sparse. Flower colors range from violet, red and pink to white. The leaves are usually palmately compound and consist of three to seven tapered leaflets.

Spider flower with white flowers
‘Helen Campbell’ is a recommended variety with white flowers
Where to plant

The Spider flower is happy in any sunny flower bed provided that the ground is not too dry. The Spider flower does not have any particular preference in terms of companion plants. Its delicate appearance goes just as well with the rounded flowers of Zinnia, Dahlia, and garden cosmos as with loose grasses or the slender flower spikes of a giant hyssop. The Spider flower also looks wonderful alongside the umbels of bishop’s weed, the "umbrella" of a radiant red coneflower, and purple top (Verbena bonariensis). At a height of up to 5 feet, tall varieties tower above many of their neighbors in the flower bed and have an incredible luminosity, especially in the backlight of the morning and evening sun. They also look wonderful in a vase and last for a long time. Recommended varieties are ’Helen Campbell' (white), 'Kirschkönigin' (carmine pink), and 'Violettkönigin' (violet).

Spider flowers can also be grown on their own in pots. If you have a spare pot, the best options are ’Señorita Rosalita' (pink), ’Señorita Carolina' (light pink), or ’Señorita Blanca' (white). Compared to other Spider flowers, these three varieties remain shorter, grow bushier, and do not have thorns.

Location and Soil

A sunny location is important – after all, as a South American the Spider flower is used to a warm climate. It can even tolerate short periods of dryness. The soil should be moderately dry to fresh and very permeable, waterlogging should be avoided at all costs.

Sowing

Seeds should be sown indoors from March at a temperature of 65 to 68 degrees Fahrenheit. The plants can be moved outdoors from mid-May. Prune young Spider flowers to encourage the formation of new shoots. As the plants naturally grow upright and remain unbranched, several plants should be grouped together (planting distance 15 inches). They also develop a great color effect, even from a distance. If you don’t want to sow your own Spider flowers, you can buy young plants from stores in April/May.

Care

If you give the Spider flower a regular dose of liquid fertilizer, it will thank you with an abundance of flowers until the onset of frost. Regularly remove seed pods so that flower formation does not decline. However, if you want, you can also leave a few pods to ripen so that you have seeds for next year.

Spider flowers alongside coneflowers
Its airy flowers and pinnate leaves give the Spider flower (Cleome spinosa) a very unique charm. Accompanied here by the yellow Coneflower
Diseases and Pests

It is normal for the leaves and stems of the robust plant to feel sticky, and this is not a sign of an aphid infestation: They have glands that secrete a sticky substance. This also seems to be effective at protecting the plants against snails and slugs. They are however occasionally infested by the Black vine weevil. Its larvae can damage the roots so severely that the plants wilt and die off.