<em>Impatiens</em>, Sunpatiens: planting, sowing, caring for

Description and botany

Impatiens, also called Busy Lizzie or Balsam, is a perennial herbaceous plant belonging to family Balsaminaceae, native to marshy forests or humid, shaded places in tropical and warm temperate regions.

Frost-tender, it is grown as an annual in gardens under our latitudes or as a houseplant because this non-hardy perennial does not withstand our winters and perishes at first frosts.

Genus includes more than 900 species. Oldest species grown in gardens is Impatiens balsamina, or garden balsam, which has produced numerous cultivars, notably double-flowered camellia-like forms. Impatiens walleriana and its hybrids are also common, as is Impatiens niamniamensis, the striking “parrot’s beak” from Congo, which bears flowers with a spur and also occurs in several varieties.

Hybridization work has led to development of SunPatiens® (Impatiens x hawkeri), hybrids derived in part from Impatiens hawkeri of New Guinea, now indispensable for being more sun-tolerant, such as the ‘Compact’ series.

With fast growth, impatiens form within months a bushy clump about 25–80 cm tall on average with nearly the same spread. While a few species such as I. glandulifera (Himalayan balsam) can reach 2 m and others are creeping like Impatiens repens, most modern hybrids offer a pretty compact, often very ramified ball-shaped habit.

Hybrids of I. walleriana show a more spreading habit. If most impatiens cannot be grown in open ground because of their frost-tender nature, Impatiens arguta has a more vigorous crown with tuberous roots, surviving temperatures of -12 to -15 °C.

Stems, easily broken and almost fleshy, thick and stiff, sometimes tinged red, bear numerous leaves alternate, opposite or whorled measuring 2 to 20 cm long, carried on a long petiole. Generally narrow, ovate or elliptical with a pointed tip, with a crenate lamina and slightly dentate margins, leaves range from pale green to dark green. Some varieties, notably New Guinea types, display very decorative foliage tinged bronze, yellow or variegated.

Some flowers: Impatiens Compact Hot Lilac, Impatiens puberula, Impatiens Compact Orchid Blush, Impatiens Compact White, Impatiens niamniamensis

This luxuriant, fleshy and glossy foliage, sometimes slightly translucent, is indeed covered by numerous flowers from June until first frosts in garden or year-round indoors away from frost. From late spring, long-pedicelled flowers appear solitary in leaf axils or grouped in small clusters of 2 to 6, renewing until autumn.

Flowers measure 2–6 cm in diameter and are made up of five heart-shaped petals. Semi-double or double, reminiscent of the plump form of tiny camellias, single and flat, sometimes galea-shaped or bearing a recurved spur as in the very unusual Impatiens niamniamensis with hooked flowers evoking parrot beaks, flower form varies with variety and hybrid.

Single-coloured or bi-coloured, flowers offer an endless range of bright, sparkling hues, perfectly set off by dense foliage.

Shades range from pastels to almost garish, from pure white, purple, lavender blue through every shade of pink and red, scarlet, crimson to yellow or coral. With a silky, velvety texture, some impatiens petals are subtly marbled or marginate and may even display a maculate throat in a contrasting tone.

This extremely generous flowering, sometimes slightly scented, gives way in autumn to dehiscent fruits that burst open suddenly, violently ejecting their seeds when ripe; it is this rapid seed discharge that gave the plant its name, impatiens!

This frost-tender perennial does not withstand sub-zero temperatures, which is why, in our climates, it is grown as an annual in open ground or in pots. While impatiens long preferred semi-shaded, even shaded spots, new hybrids such as SunPatiens® now tolerate full sun very well and adapt equally to cool climates and to our warmest regions.

In a fresh, rich soil, impatiens offer incomparable floribundity and are almost maintenance-free!

With their fresh or lively colours, these summer flowers are ideal for shady garden scenes, enhancing all summer displays in beds, in borders along a path or wall, at edge of a wood, in a window box on a sill or in pots on a terrace or near entrances.

Impatiens are thought to possess air-purifying properties.

Main species and varieties

Most popular

Our favourites

Another interesting variety

Impatiens Sunpatiens Compact Blush Pink - Busy Lizzie

A very floriferous Impatiens regarded as one of the best. It tolerates sun and will form a flowering ball in pots or your summer beds.

• Flowering time July to November
• Height at maturity 25 cm

See the product sheet

Impatiens SunPatiens Compact Purple

A hybrid impatiens with vivid, intense colours from June through to the first frosts. Plant in window boxes or along sunny paths.

• Flowering time July to October
• Height at maturity 60 cm

See the product sheet

Impatiens niamniamensis

A tender perennial with unusual bicoloured flowers. It provides an exotic display in shaded beds or indoors or in a conservatory, even in mid-winter.

• Flowering time July to December
• Height at maturity 60 cm

See the product sheet

Impatiens Sunpatiens Compact Hot Lilac - Busy Lizzie

A hybrid impatiens covered in bright lilac-pink flowers for six months. Ideal for summer arrangements thanks to its compact habit.

• Flowering time July to November
• Height at maturity 40 cm

See the product sheet

Impatiens Sunpatiens Compact Electric Orange

A hybrid variety with a compact habit and vibrant orange colour. Ideal for summer arrangements, in window boxes or along paths, in planters and border beds.

• Flowering time July to November
• Height at maturity 50 cm

See the product sheet

Impatiens Sunpatiens Compact Orchid Blush - Busy Lizzie

We love its delicate pale mauve-pink flowers. Charming in planters and border beds.

• Flowering time July to November
• Height at maturity 50 cm

See the product sheet

Selection of 5 Sunpatiens Impatiens

An exclusive collection of five disease- and sun-resistant Impatiens! Well suited to beds, pots, borders and planters.

• Flowering time July to November
• Height at maturity 25 cm

See the product sheet

Impatiens walleriana F2 Colour Cocktail Mix - Busy Lizzie

An exceptionally charming mix of impatiens to brighten shaded areas with vivid flowers. Easy to sow in a bed or shaded borders, never in full sun.

• Flowering time July to November
• Height at maturity 20 cm

See the product sheet

Impatiens puberula

One of the rare perennial impatiens! Very unusual, it is fully hardy in your garden.

• Flowering time August to November
• Height at maturity 15 cm

See the product sheet

Planting

Where to plant impatiens?

Impatiens is a frost-tender perennial plant that does not tolerate sub-zero temperatures and must be brought indoors over winter as it dies at 0 °C. That is why it is grown in the garden as an annual in open ground, disappearing at the first frosts, or grown as a tender indoor perennial (keep warm over winter at a minimum of 10–15 °C) and offering flowering all year round.

Pots can be taken outside in fine weather as soon as temperatures rise above 15 °C and frosts are no longer a risk.

Although recent hybrid selections tolerate sun better, impatiens remain one of the surest choices among summer shade flowers, the only annual capable of flowering in full shade. Hybrids withstand non-scorching exposures quite well if their roots stay cool during summer.

In pots outdoors, protect from wind.

Like any tropical plant, it prefers humid conditions and will be particularly comfortable in a greenhouse or conservatory with filtered light without direct sun and sheltered from draughts.

It is easy to grow in fresh, humus-bearing and well-drained soil as it tolerates neither drought nor stagnant moisture.

An outstanding summer shade flower to flower throughout the season in cool, shaded corners of the garden, impatiens can be planted indifferently in pots or window boxes as well as in open ground, in groups at the edge of a bed of bushes, perennials or annuals, at the woodland edge, to highlight ephemeral path borders. Low cultivars (10–15 cm high) or new hybrids with a very compact habit make attractive groundcovers.

They are also good indoor plants for conservatory use and can be kept for many years.

Impatiens are excellent groundcovers for shade!

When to plant impatiens?

Planting our Impatiens plug plants is done in spring from April to May, or even June depending on region, in all cases after the last frosts, in open ground or in pots. Planting is possible under cover from March onwards.

How to plant impatiens?

On receipt, pot up and keep our Impatiens plug plants under cover and let them gain vigour for a few weeks before placing outside once frost risk has passed.

In open ground

Allow about 8 to 10 plants per m2, spaced at least 20 cm in all directions. Plant in quantity to obtain large flowering drifts under trees, for example. Plant in staggered rows. Soil must be fertile and well drained.

• Fork over soil to half spade depth
• Dig a hole 2 to 3 times larger than the size of the plug (about 15 cm deep)
• Make a good bed of gravel for perfect drainage
• Mix the excavated soil with geranium potting compost and coarse sand
• Place plug plant in centre of the hole, collar level with soil surface
• Bring soil back in to surround the roots
• Firm down with the foot
• Water copiously

In a pot

Most impatiens are the kings of summer window boxes and containers! Mix varieties! Space plug plants 20–25 cm apart for a dense, lively display.

• Soak plugs well before planting
• Line container base with gravel or clay pebbles
• Plant in geranium-type potting compost mixed with river sand. Fill gaps
• Firm without damaging plug
• Water copiously then regularly but without excess as surface soil dries
• Bring pot indoors in autumn to protect from frost if you wish to keep plant as a perennial and put back out in May, avoiding very strong sun

More tips on our blog to succeed with planting plug plants in window boxes!

Impatiens Compact Lilac in pot

When and how to sow impatiens seeds?

Under cover

Sow the impatiens seeds from March under heated cover. Your plants will flower after about 6 weeks.

• In a seed tray sow seeds on the surface without burying, in a mix of potting compost and heather soil
• Place in light in a warm place at 16 to 21°C
• Keep substrate moist but not waterlogged until germination within 18 to 21 days
• Keep seedlings warm until mid-May
• Transplant outdoors spacing 0.30 m, or into pots or window boxes after any risk of frost has passed, adding compost to each planting hole

Direct sowing

• In May, in well-worked soil enriched with compost, sow your impatiens seeds broadcast once any risk of frost has passed
• Cover lightly with potting compost without burying
• Firm down
• Water generously with a fine spray
• Thin seedlings leaving one young plant every 30 to 50 cm
• Pinch out shoot tips to encourage young impatiens to ramify

→ Learn more in our tutorial : How to sow impatiens ?

Maintenance, pruning and care

Impatiens is an annual, floriferous plant that is carefree and above all almost maintenance-free provided it is regularly fed with fertiliser and well watered!

In open ground

Impatiens does not tolerate drought. Watering should be regular, especially when it does not rain and weather is dry, without being excessive, once or twice a week, because roots are sensitive to excess moisture, which causes root rot.

Remove faded flowers and dry stems regularly to keep an attractive appearance and encourage flowering.

Very frost-tender, plant perishes with first frosts and must be renewed each year in garden: lift clumps unless you wish to keep them. In that case, cut plant back to soil level, pot up and store in a warm, frost-free place out of direct sunlight: indoors, flowering is almost continuous when pot is kept above 15°C.

Impatiens Compact White

Care for an Impatiens in a pot

With rapid growth, it is a heavy feeder: water once a week, allowing soil to dry between waterings to avoid any risk of rotting; likewise, do not let water stagnate in saucers.

Indoors, ensure high humidity as foliage and flowers wilt quickly if ambient air is too dry: optionally place pots on a bed of clay pebbles to increase air humidity this tropical plant needs indoors.

Apply a liquid fertiliser once or twice a month during growth. Water sparingly in winter without letting root ball dry out and keep room temperature between 10-15°C.

Pruning is not necessary, Impatiens naturally retains a lovely compact, globular habit: in spring, simply cut back stems that tend to thin at the base to encourage new shoots and renew flowering.

Repot if necessary every 2 years in spring and give it time outdoors in a shaded position from May to September. You can also transplant it into open ground for the summer within a shaded bed or border.

Possible diseases and pests

Resistant to disease, impatiens are not much troubled. Outdoors, remember to protect them from slugs which favour their young foliage and read our tips to keep gastropods away!

Avoid excess water at all costs, which can cause grey mould (Botrytis) of the collar, main stem and flower buds: always allow the soil to dry out between waterings. If affected: repot into a free-draining, not waterlogged mix and water sparingly.

Impatiens grown in greenhouse or conservatory are susceptible to red spider mites, which develop in a warm, dry atmosphere and cause yellowing followed by leaf drop: spray non-calcareous water regularly over foliage to maintain a humid environment around the pot to help prevent infestations. If infestation occurs: carry out sprays of soapy water.

Indoors, they can also suffer attacks from aphids and whiteflies during summer: significantly shorten infested stems and spray with soapy water that is non-calcareous.

Propagation

Spontaneous sowing is common, impatiens seeds reseed easily when conditions are favourable. If propagation of impatiens can be done by sowing (with seeds harvested in autumn), propagation by cuttings by herbaceous cuttings in May–June remains a quick and simple way to obtain new plants.

How to take Impatiens cuttings?

• Take 7–10 cm stem cuttings
• Place them in a glass of water indoors
• After two to three weeks, when roots have appeared, replant cuttings into buckets filled with damp turf and coarse sand
• Keep warm and frost-free during winter (minimum 15°C) and plant out next spring into ground or into pot after last frosts

Companion plants for Impatiens

With their bright or pastel colours, Impatiens are among those annuals essential in summer in shaded garden scenes, bringing cheer and charm.

An idea for a shaded planting: Digitalis purpurea, Hydrangea macrophylla ‘Black Steel Zebra’, Impatiens Compact White, Polystichum setiferum ‘Proliferum’, Geranium nodosum

They fit easily into city gardens, natural or naturalistic gardens or romantic gardens, creating bright, fresh and often very colourful compositions. With them, shade is not necessarily a sign of dull or washed-out colours!

In groups, they are easy to combine with other summer-flowering perennials for shade or partial shade or with annuals, quickly forming beautiful, imposing colourful masses alongside Astrantias, Japanese Anemones, Fuchsias and Ammi.

Impatiens compete in beauty with plants bearing bronze, silver or yellow‑green foliage, harmonising with Anthirrhinum, Diascias, Helichrysum petiolare, Tobaccos and verveins with spreading habit.

An idea for a trough: Impatiens Compact Hot Lilac, Heuchera ‘Purple Petticoats’ and Impatiens Compact Orchid Blush

Plant them at front of a border with small grasses such as fescues.

In a woodland-understorey setting, punctuate a tapetum of Heucheras and Hostas with a few Impatiens and mix them with bulbs to naturalise in shade!

Paired with Hydrangeas and pelargoniums, they will hide bare bases of shrub roses throughout the season in a fresh, romantic scene of a pink garden or white.

In pots on a shaded terrace, combine them with other annuals such as coleus, begonias or ipomoeas.