‘Rainbow’ Gladiolus

Name: ‘Rainbow’ Gladiolus
Brand: Van Noort
SKU: VAN-331-113-01
Price: 8.49 CAD
Availability: OutOfStock

Sale Sold out

Fifteen ‘Rainbow’ gladioli raise spikes about 100 cm tall above sword-shaped green leaves

Summer-flowering perennial corms Iridaceae

Multicoloured gladiolus mix for borders and bouquets

Van Noort

Common name‘Rainbow’ gladiolus

FamilyIridaceae

GenusGladiolus

SpeciesHorticultural hybrid

CultivarRainbow

Bulb typeSummer-flowering perennial corms

Botanical nameGladiolus

Quantity per pack15 size 12/14 corms

‘Rainbow’ Gladiolus (Gladiolus × hortulanus) ‘Rainbow’ gladiolus brings together fifteen size 12/14 corms in an assortment of large red, pink, yellow, orange, white, and purple flowers. In late summer, ruffled florets open gradually from the base toward the top of upright spikes, renewing colour over several days. Narrow green sword-shaped foliage forms a graphic base below the blooms. Each plant reaches about 100 cm tall with a 10 cm spread. This Van Noort format suits sunny beds, vertical borders, and dedicated cutting gardens especially well, where the range of colours produces spontaneous bouquets without sacrificing the visual unity of the planted group or its strong architectural summer presence.

Plant corms in spring once frost danger has passed and the soil has warmed. Set them pointed end upward about 10 cm deep and 10 cm apart in fertile, loose, freely drained soil. Choose full sun and a position sheltered from strong gusts. Water after planting, then deeply whenever the surface begins to dry, without holding water around the corms. Divide the fifteen corms into three groups of five planted ten to fourteen days apart to stagger the arrival of spikes. Install slim stakes before buds become heavy and feed moderately without excessive nitrogen. Keep weeds controlled so young shoots receive light, air, and steady access to moisture.

Cut stems early in the morning when the lowest two buds show colour, while retaining several leaves on the plant to feed the replacement corm. Refresh vase water often and remove faded florets. In the garden, varied tones pair naturally with white cosmos, blue salvias, pink coneflowers, burgundy dahlias, and golden grasses. Open flowers attract bees and butterflies. In cold Canadian climates, this zone 8 gladiolus is grown as a tender annual. After the first frost, lift the corms, let them dry, clean them, and store them somewhere cool, dry, dark, airy, and completely frost-free. Inspect the stored group occasionally and discard any soft or spotted specimen.

In the garden

Exposure: Full sun
Life cycle: Tender perennial grown as an annual in colder Canadian regions

Planting guide

Planting & establishment

Planting depth

Approximately 10 cm (4 in.)

Spacing / density

space 10 to 15 cm (4 to 6 in.)

Planting period

May to June in colder Canadian regions, once soil has warmed

Propagation

Corms and separation of cormlets during dormancy

Growing method

Plant all fifteen corms in spring after frost danger has passed and the soil begins to warm. Choose a position receiving at least six hours of sun and sheltered from prevailing winds. Loosen the soil, incorporate mature compost, and improve drainage wherever water lingers. Set corms pointed end upward about 10 cm deep and 10 cm apart. Water to settle soil around them, then maintain even moisture without saturation. To extend flowering, divide planting into two or three dates spaced two weeks apart. Add discreet support in exposed locations. Remove faded spikes but retain several leaves so reserves return to each corm. After foliage yellows, lift before hard frost, dry and clean the corms, and store them in a cool, dry, dark, frost-free place. Inspect stored corms periodically and discard any that soften or develop mould. During summer, water at soil level in the morning and avoid wetting foliage unnecessarily. Watch for thrips that can scar flowers and remove badly affected tissue promptly. A thin mulch layer suppresses weeds, but keep it away from stem bases. Label the group before the foliage disappears, and clean cutting tools between plants to reduce disease spread during harvest.

Soil and care

Soil & care

Soil pH

Acid, neutral, or alkaline

Moisture

Maintain moderate, even moisture during rooting, active growth, and spike formation. Water deeply when the upper few centimetres of soil become dry, then allow excess water to drain away. Avoid constantly waterlogged ground, which encourages corm rot, and prolonged drought while flowers are developing. Reduce irrigation gradually as foliage yellows so the corms can mature before dormancy, lifting, drying, and frost-free storage.

Minimum temperature

Avoid frost; lift before hard freezes

Care level

Moderate

Watering

After planting, water to settle the soil, then wait for shoots before increasing irrigation. During active growth and flowering, provide approximately 2.5 cm (1 in.) of water weekly when rain is absent. Water at soil level in the morning and let the surface drain. Reduce moisture gradually after bloom so corms mature before dormancy. Consistent moisture supports even spikes. Containers may need more frequent checks during hot, windy weather.

Soil type

Choose light, freely drained soil in full sun. Loam, sand, or chalk at any pH is suitable when excess water drains quickly. Avoid cold saturated clay, especially during dormancy. In a borderline climate, the base of a south- or west-facing wall creates a warmer sheltered microclimate and reduces winter moisture around the corms. Add fine gravel where necessary to improve soil structure and protect dormant corms from prolonged winter wetness.

Fertilization

Incorporate mature compost before planting. When shoots reach 10 to 15 cm (4 to 6 in.), apply balanced slow-release fertilizer or a half-strength liquid feed. Repeat once as buds begin forming. Avoid excess nitrogen, which promotes foliage and weak stems at the expense of flowers and the corm’s stored energy. Stop feeding after bloom so foliage can mature naturally and corms can enter dormancy with firm, well-ripened tissues.

Seasonal care

In spring, inspect corms and discard any that are soft, mouldy, or badly shrivelled. Prepare a full-sun site enriched with compost and offering excellent drainage. Plant about 10 cm deep and 10 cm apart, then water. During growth, weed carefully, maintain even moisture, and watch for thrips, aphids, and slugs. Apply a moderate dose of balanced fertilizer when shoots reach 10 to 15 cm. Stake only spikes exposed to wind. For bouquets, cut when the two lowest florets show colour while leaving several leaves. Remove faded flowers afterward without stripping green foliage. In fall, reduce irrigation and wait for natural yellowing. Lift corms before hard frost, dry them in an airy location, remove soil and old tissues, and label the cultivar. Store in paper bags or ventilated trays in a cool, dry, dark, frost-free place. Check monthly and discard every softened, spotted, or mouldy corm before spring. In early summer, confirm that the soil still drains freely after heavy rain and gently loosen any crusted surface. Avoid high-nitrogen feeding that creates weak stems. During storage, do not stack corms in thick layers, and maintain steady air circulation. The following spring, plant only firm, healthy corms after the ground has warmed. Separate small cormlets if desired, but expect them to require additional growing seasons before flowering. Choose a clean, ventilated storage shelf.

Container growing

Recommended pot size

heavy pot, 45 to 55 cm (18 to 22 in.) in diameter and at least 35 cm (14 in.) deep for a group of 5 to 7 corms

To grow all fifteen corms in a container, choose a heavy pot at least 40 cm wide and 35 cm deep with several drainage holes. Use quality potting mix blended with mature compost and coarse perlite. Set corms pointed end upward about 10 cm deep and distribute them evenly. Water after planting, then whenever the surface begins to dry, never allowing water to remain in the saucer. Place the pot in full sun, shelter it from strong gusts, and rotate it to encourage straight growth. Add a discreet circular support before spikes lengthen. Apply a half-strength balanced fertilizer during active growth. Remove faded flowers but allow leaves to yellow, then stop watering. Before frost, move the container into a cool, dry place or lift the corms and store them separately in frost-free conditions. Monitor moisture more closely on hot days because containers dry faster than garden soil. Water slowly until moisture exits the drainage holes, then empty the saucer. Move the pot away from walls that reflect excessive heat and inspect leaves regularly for thrips. During storage, keep the growing medium nearly dry to prevent rot, and ensure that air can circulate around the pot or lifted corms.

Size, flowering & harvest

Mature height

100 cm (40 in.)

Width / spread

10 cm (4 in.)

Flower color

Red, pink, yellow, orange, white, and purple

Foliage color

Green

Foliage type

Deciduous, narrow, upright, and sword-shaped

Growth rate

Moderate

Growth habit

Upright, columnar, and clump-forming

Fragrance

Light or absent; grown primarily for colour

Bloom period

From midsummer into late summer, upright spikes carry large, funnel-shaped flowers in a mixture of red, yellow, pink, purple, orange, and white. Ruffled florets open gradually from bottom to top. Green sword-shaped foliage reinforces the vertical silhouette. Cut several spikes when the first buds show colour, or leave them to animate a sunny border, large containers, cutting garden, and lively seasonal planting.

Harvest

July to September

Garden associations

Companion plants & uses

Companion plants

Choose dahlias, compact cannas, salvias, verbenas, cosmos, zinnias, and fine grasses that share a preference for sun, warmth, and draining soil. Purple or bronze foliage echoes the dark flower throat, while blue blooms provide a cool contrast. Avoid bog plants and dense groundcovers that trap moisture around corms or complicate cormlet division. Yarrows and bearded irises extend the early-summer display around the spikes. Leave open soil around each cluster so lifting tools can enter without damaging neighbouring crowns, and maintain clear airflow during humid weather.

Garden use

Place Rainbow near the middle or back of a sunny border where its roughly 100 cm spikes can rise above shorter perennials. Arrange all fifteen corms in two staggered rows or irregular clusters for a natural appearance and useful visual support. Combine the red, yellow, pink, purple, orange, and multicoloured flowers with white cosmos, purple sages, apricot zinnias, burgundy dahlias, and golden grasses. Avoid direct competition from vigorous shrub roots. In a cutting garden, position the group beside an access path so spikes can be harvested without trampling shoots. For containers, use a heavy pot near a sunny terrace. Planting batches two weeks apart extends both the garden display and bouquet season. After flowering, let foliage mature behind fuller companions, then lift corms before hard frost and store them in cool, dry, dark, frost-free conditions until spring. For a more cohesive effect, repeat several pale-soft blue accents among neighbouring plants without using exactly the same height. Grey or purple foliage highlights the gently ruffled petals. Leave enough room to reach spikes with clean pruners and to move around them when staking. A durable label prevents accidental disturbance and helps return the stored corms to the same composition the following spring.

Frequently asked questions

How should the fifteen Rainbow corms be planted?

Plant in spring after frost danger has passed and the soil has warmed. Sort the fifteen corms and retain firm specimens. Set the flatter side downward and the point upward about 10 cm deep and 10 cm apart. Choose full sun and fertile, freely drained soil, then water to settle soil around the corms without saturating it. To extend the display, make three groups of five and space planting dates ten to fourteen days apart. Mark the row and install supports early if the position receives strong winds. Keep the area weeded and evenly moist as shoots emerge and roots establish.

Which colours actually make up Rainbow?

The assortment generally includes red, pink, yellow, orange, white, and purple among large ruffled flowers. Because it is a living mixture, the exact number of spikes in each colour may vary with the package and the performance of individual corms. Light, temperature, and floret age may also shift observed intensity slightly. Group plants so all tones read as one composition instead of isolated points. White cosmos, blue salvias, and golden grasses provide a calm background that highlights the diversity without making the bed appear disorganized. Each flowering group will therefore develop its own natural balance while retaining the intended rainbow effect. The contrast remains clearly visible from the garden path.

How can straight, sturdy spikes be encouraged?

Set corms about 10 cm deep in firm but drained soil so roots can anchor stems well. Full sun limits weak stretching caused by shade. In a windy position, install slim stakes or support netting before developing buds become heavy. Water deeply instead of shallowly and avoid excessive nitrogen, which produces soft tissues. A compact group also provides partial shelter while maintaining 10 cm spacing and good airflow. Inspect ties regularly so they never constrict expanding spikes, and adjust supports promptly after storms or heavy summer rain. Rotate large containers occasionally so every stem receives balanced light and does not lean strongly in one direction. Keep young shoots protected from slugs during early growth.

When should Rainbow be cut for a bouquet?

Cut early in the morning when the lowest two buds show colour and begin opening while upper buds remain firm. Use a clean tool and leave at least four leaves on each plant to feed its replacement corm. Place stems immediately in fresh water, recut them at an angle, and remove only foliage that would sit below the waterline. In the vase, refresh water often and remove faded florets. Keep the bouquet away from direct sun, heat sources, and ripening fruit so the multicoloured spikes continue opening gradually and retain their freshness. Combine them with simple foliage to let every flower colour remain clearly visible.

How should the corms be stored through winter?

After the first frost, cut stems while leaving a short section and lift corms without injuring them. Shake away soil, label ‘Rainbow’ immediately, and let clusters dry in sheltered airflow. When tissues are dry, remove the shrivelled old corm and small cormels, then discard soft, spotted, or foul-smelling specimens. Store sound corms in one layer or breathable paper bags somewhere cool, dry, dark, and frost-free. Inspect them several times through winter and remove any deteriorating piece to protect the remainder of the multicoloured group. Replant only firm, healthy corms after spring soil warms and frost danger has passed. Keep every stored batch dry and correctly labelled.

Wildlife and pets

Wildlife & precautions

Attracts birds

Yes

Reported toxicity

Yes

Supporting wildlife

Funnel-shaped flowers may attract daytime butterflies and some long-tongued pollinators, while mixed colours colouring signals blooms to insects active near dusk. This contribution is complementary within a diverse garden. Avoid insecticides, retain several uncut spikes, and grow nearby nectar plants with more accessible flowers to support a broader range of visitors.